Powered surgical instruments with firing system lockout arrangements

ABSTRACT

Surgical instruments and/or fastener apparatuses comprising an end effector with a pair of jaws pivoted at a proximal end thereof and movable between an open and closed position. At least one of the jaws may comprise a channel for receiving a cartridge containing a plurality of surgical fasteners. Also, an electrically powered actuator may be for deploying the surgical fasteners and may comprise a power source and a motor. An activation mechanism may be attached to the handle to move the pair of jaws from the open to the closed position and to activate the actuator. A lockout mechanism may be configured to permit current to flow from the power source to the motor when the pair of jaws is in the closed position and to prevent current from flowing to the power source to the motor when the pair of jaws is in the open position.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation application claiming priority under35 U.S.C. § 120 to U.S. patent application Ser. No. 16/420,870, entitledPOWERED SURGICAL INSTRUMENTS WITH FIRING SYSTEM LOCKOUT ARRANGEMENTS,filed May 23, 2019, now U.S. Patent Application Publication No.2019/0343514, which is a continuation application claiming priorityunder 35 U.S.C. § 120 to U.S. patent application Ser. No. 15/864,922,entitled POWERED SURGICAL INSTRUMENTS WITH FIRING SYSTEM LOCKOUTARRANGEMENTS, filed Jan. 8, 2018, which issued on Jun. 9, 2020 as U.S.Pat. No. 10,675,028, which is a continuation application claimingpriority under 35 U.S.C. § 120 to U.S. patent application Ser. No.13/796,996, entitled POWERED SURGICAL INSTRUMENTS WITH FIRING SYSTEMLOCKOUT ARRANGEMENTS, filed Mar. 12, 2013, which issued on Jan. 9, 2018as U.S. Pat. No. 9,861,359, which is a continuation-in-part applicationclaiming priority under 35 U.S.C. § 120 to U.S. patent application Ser.No. 13/424,648, entitled SURGICAL INSTRUMENT HAVING RECORDINGCAPABILITIES, filed Mar. 20, 2012, which issued on Jun. 17, 2014 as U.S.Pat. No. 8,752,747, which is a divisional application claiming priorityunder 35 U.S.C. § 121 to U.S. patent application Ser. No. 12/949,099,entitled SURGICAL INSTRUMENT HAVING RECORDING CAPABILITIES, filed Nov.18, 2010, which issued on May 1, 2012 as U.S. Pat. No. 8,167,185, whichis a continuation application claiming priority under 35 U.S.C. § 120 toU.S. patent application Ser. No. 11/343,803, entitled SURGICALINSTRUMENT HAVING RECORDING CAPABILITIES, filed Jan. 31, 2006, whichissued on Dec. 7, 2010 as U.S. Pat. No. 7,845,537, the entiredisclosures of each are hereby incorporated by reference herein. Thisapplication is also a continuation application claiming priority under35 U.S.C. § 120 to U.S. patent application Ser. No. 16/420,870, entitledPOWERED SURGICAL INSTRUMENTS WITH FIRING SYSTEM LOCKOUT ARRANGEMENTS,filed May 23, 2019, now U.S. Patent Application Publication No.2019/0343514, which is a continuation application claiming priorityunder 35 U.S.C. § 120 to U.S. patent application Ser. No. 15/864,922,entitled POWERED SURGICAL INSTRUMENTS WITH FIRING SYSTEM LOCKOUTARRANGEMENTS, filed Jan. 8, 2018, which issued on Jun. 9, 2020 as U.S.Pat. No. 10,675,028, which is a continuation application claimingpriority under 35 U.S.C. § 120, to U.S. patent application Ser. No.13/796,996, entitled POWERED SURGICAL INSTRUMENTS WITH FIRING SYSTEMLOCKOUT ARRANGEMENTS, filed Mar. 12, 2013, which issued on Jan. 9, 2018as U.S. Pat. No. 9,861,359, which is also a continuation-in-partapplication claiming priority under 35 U.S.C. § 120 to U.S. patentapplication Ser. No. 12/846,228, entitled MOTOR DRIVEN SURGICAL FASTENERDEVICE WITH CUTTING MEMBER LOCKOUT ARRANGEMENTS, filed Jul. 29, 2010,now U.S. Patent Application Publication No. 2011/0006101, which is acontinuation-in-part application claiming priority under 35 U.S.C. § 120to U.S. patent application Ser. No. 12/693,460, entitled DRIVEN SURGICALSTAPLER IMPROVEMENTS, filed Jan. 26, 2010, now U.S. Patent ApplicationPublication No. 2011/0024477, which claims the benefit from U.S.Provisional Patent Application Ser. No. 61/150,382, entitledMOTOR-DRIVEN SURGICAL STAPLER IMPROVEMENTS under 35 U.S.C. § 119(e),filed on Feb. 6, 2009, the entire disclosures of each are herebyincorporated by reference herein. This application is also acontinuation-in-part application claiming priority under 35 U.S.C. § 120to U.S. patent application Ser. No. 16/420,879, entitledROBOTICALLY-CONTROLLED END EFFECTOR, filed May 23, 2019, now U.S. PatentApplication Publication No. 2019/0343515, which is a continuationapplication claiming priority under 35 U.S.C. § 120, to U.S. patentapplication Ser. No. 14/298,252, entitled SURGICAL STAPLING SYSTEMCOMPRISING AN ANVIL SENSOR, filed Jun. 6, 2014, now U.S. PatentApplication Publication No. 2014/0284371, which is a continuationapplication claiming priority under 35 U.S.C. § 120 to U.S. patentapplication Ser. No. 13/372,195, entitled ROBOTICALLY-CONTROLLED ENDEFFECTOR, filed Feb. 13, 2012, now U.S. Patent Application PublicationNo. 2012/0292367, which is a continuation-in-part application claimingpriority under 35 U.S.C. § 120 to U.S. patent application Ser. No.13/118,272, entitled ROBOTICALLY-CONTROLLED SURGICAL INSTRUMENT WITHFORCE-FEEDBACK CAPABILITIES, filed May 27, 2011, now U.S. PatentApplication Publication No. 2011/0290856, which is acontinuation-in-part application claiming priority under 35 U.S.C. § 120to U.S. patent application Ser. No. 12/949,099, entitled SURGICALINSTRUMENT HAVING RECORDING CAPABILITIES, filed Nov. 18, 2010, whichissued on May 1, 2012 as U.S. Pat. No. 8,167,185, which is acontinuation application claiming priority under 35 U.S.C. § 120 to U.S.patent application Ser. No. 11/343,803, entitled SURGICAL INSTRUMENTHAVING RECORDING CAPABILITIES, filed Jan. 31, 2006, which issued on Dec.7, 2010 as U.S. Pat. No. 7,845,537, the entire disclosures of each arehereby incorporated by reference herein.

The present application is related to the following U.S. patentapplications, the entire disclosures of each are incorporated herein byreference:

U.S. patent application Ser. No. 11/343,498, now U.S. Pat. No.7,766,210, entitled MOTOR-DRIVEN SURGICAL CUTTING AND FASTENINGINSTRUMENT WITH USER FEEDBACK SYSTEM, Inventors: Frederick E. Shelton,IV, John Ouwerkerk and Jerome R. Morgan;

U.S. patent application Ser. No. 11/343,573, now U.S. Pat. No.7,416,101, entitled MOTOR-DRIVEN SURGICAL CUTTING AND FASTENINGINSTRUMENT WITH LOADING FORCE FEEDBACK, Inventors: Frederick E. Shelton,IV, John N. Ouwerkerk, Jerome R. Morgan, and Jeffrey S. Swayze;

U.S. patent application Ser. No. 11/344,035, now U.S. Pat. No.7,422,139, entitled MOTOR-DRIVEN SURGICAL CUTTING AND FASTENINGINSTRUMENT WITH TACTILE POSITION FEEDBACK, Inventors: Frederick E.Shelton, IV, John N. Ouwerkerk, Jerome R. Morgan, and Jeffrey S. Swayze;

U.S. patent application Ser. No. 11/343,447, now U.S. Pat. No.7,770,775, entitled, MOTOR-DRIVEN SURGICAL CUTTING AND FASTENINGINSTRUMENT WITH ADAPTIVE USER FEEDBACK, Inventors: Frederick E. Shelton,IV, John N. Ouwerkerk, and Jerome R. Morgan;

U.S. patent application Ser. No. 11/343,562, now U.S. Pat. No.7,568,603, entitled MOTOR-DRIVEN SURGICAL CUTTING AND FASTENINGINSTRUMENT WITH ARTICULATABLE END EFFECTOR, Inventors: Frederick E.Shelton, IV and Christoph L. Gillum;

U.S. patent application Ser. No. 11/344,024, now U.S. Pat. No.8,186,555, entitled MOTOR-DRIVEN SURGICAL CUTTING AND FASTENINGINSTRUMENT WITH MECHANICAL CLOSURE SYSTEM, Inventors: Frederick E.Shelton, IV and Christoph L. Gillum;

U.S. patent application Ser. No. 11/343,321, now U.S. Patent PublicationNo. 2007/0175955, entitled SURGICAL CUTTING AND FASTENING INSTRUMENTWITH CLOSURE TRIGGER LOCKING MECHANISM, Inventors: Frederick E. Shelton,IV and Kevin R. Doll;

U.S. patent application Ser. No. 11/343,563, now U.S. Patent PublicationNo. 2007/0175951, entitled GEARING SELECTOR FOR A POWERED SURGICALCUTTING AND FASTENING STAPLING INSTRUMENT, Inventors: Frederick E.Shelton, IV, Jeffrey S. Swayze, Eugene L. Timperman;

U.S. patent application Ser. No. 11/344,020, now U.S. Pat. No.7,464,846, entitled SURGICAL INSTRUMENT HAVING A REMOVABLE BATTERY,Inventors: Frederick E. Shelton, IV, Kevin R. Doll, Jeffrey S. Swayzeand Eugene Timperman;

U.S. patent application Ser. No. 11/343,439, now U.S. Pat. No.7,644,848, entitled ELECTRONIC LOCKOUTS AND SURGICAL INSTRUMENTINCLUDING SAME, Inventors: Jeffrey S. Swayze, Frederick E. Shelton, IV,Kevin R. Doll;

U.S. patent application Ser. No. 11/343,547, now U.S. Pat. No.7,753,904, entitled ENDOSCOPIC SURGICAL INSTRUMENT WITH A HANDLE THATCAN ARTICULATE WITH RESPECT TO THE SHAFT, Inventors: Frederick E.Shelton, IV, Jeffrey S. Swayze, Mark S. Ortiz, and Leslie M. Fugikawa;

U.S. patent application Ser. No. 11/344,021, now U.S. Pat. No.7,464,849, entitled ELECTRO-MECHANICAL SURGICAL CUTTING AND FASTENINGINSTRUMENT HAVING A ROTARY FIRING AND CLOSURE SYSTEM WITH PARALLELCLOSURE AND ANVIL ALIGNMENT COMPONENTS, Inventors: Frederick E. Shelton,IV, Stephen J. Balek and Eugene L. Timperman;

U.S. patent application Ser. No. 11/343,546, now U.S. Patent PublicationNo. 2007/0175950, entitled DISPOSABLE STAPLE CARTRIDGE HAVING AN ANVILWITH TISSUE LOCATOR FOR USE WITH A SURGICAL CUTTING AND FASTENINGINSTRUMENT AND MODULAR END EFFECTOR SYSTEM THEREFOR, Inventors:Frederick E. Shelton, IV, Michael S. Cropper, Joshua M. Broehl, Ryan S.Crisp, Jamison J. Float, Eugene L. Timperman; and

U.S. patent application Ser. No. 11/343,545, now U.S. Pat. No.8,708,213, entitled SURGICAL INSTRUMENT HAVING A FEEDBACK SYSTEM,Inventors: Frederick E. Shelton, IV, Jerome R. Morgan, Kevin R. Doll,Jeffrey S. Swayze and Eugene Timperman.

BACKGROUND

The present invention relates in general to surgical instruments, andmore particularly to minimally invasive surgical instruments capable ofrecording various conditions of the instrument.

The disclosed invention relates generally and in various embodiments tosurgical stapling and cutting instruments structured and configured forapplying lines of staples from a reusable staple cartridge into tissuewhile cutting the tissue between the applied staple lines. Moreparticularly the disclosed invention relates to electronic interlocksfor use in motorized surgical stapling and cutting instruments thatprevent cutting of the tissue when the staple cartridge is notinstalled, is improperly installed, or is spent, or when the surgicalstapling and cutting instrument is not otherwise in a condition toperform a stapling and cutting operation in a safe and/or optimalmanner. The disclosed invention further relates to electronic interlocksfor disabling use of certain instrument features while a stapling andcutting operation is in progress.

Endoscopic surgical instruments are often preferred over traditionalopen surgical devices because a smaller incision tends to reduce thepost-operative recovery time and complications. Consequently,significant development has gone into a range of endoscopic surgicalinstruments that are suitable for precise placement of a distal endeffector at a desired surgical site through a cannula of a trocar. Thesedistal end effectors engage the tissue in a number of ways to achieve adiagnostic or therapeutic effect (e.g., endocutter, grasper, cutter,staplers, clip applier, access device, drug/gene therapy deliverydevice, and energy device using ultrasound, RF, laser, etc.).

Known surgical staplers include an end effector that simultaneouslymakes a longitudinal incision in tissue and applies lines of staples onopposing sides of the incision. The end effector includes a pair ofcooperating jaw members that, if the instrument is intended forendoscopic or laparoscopic applications, are capable of passing througha cannula passageway. One of the jaw members receives a staple cartridgehaving at least two laterally spaced rows of staples. The other jawmember defines an anvil having staple-forming pockets aligned with therows of staples in the cartridge. The instrument includes a plurality ofreciprocating wedges which, when driven distally, pass through openingsin the staple cartridge and engage drivers supporting the staples toeffect the firing of the staples toward the anvil.

An example of a surgical stapler suitable for endoscopic applications isdescribed in U.S. Pat. No. 5,465,895, entitled SURGICAL STAPLERINSTRUMENT to Knodel et al., which discloses an endocutter with distinctclosing and firing actions. A clinician using this device is able toclose the jaw members upon tissue to position the tissue prior tofiring. Once the clinician has determined that the jaw members areproperly gripping tissue, the clinician can then fire the surgicalstapler with a single firing stroke, or multiple firing strokes,depending on the device. Firing the surgical stapler causes severing andstapling of the tissue. The simultaneous severing and stapling avoidscomplications that may arise when performing such actions sequentiallywith different surgical tools that respectively only sever and staple.

One specific advantage of being able to close upon tissue before firingis that the clinician is able to verify via an endoscope that thedesired location for the cut has been achieved, including a sufficientamount of tissue has been captured between opposing jaws. Otherwise,opposing jaws may be drawn too close together, especially pinching attheir distal ends, and thus not effectively forming closed staples inthe severed tissue. At the other extreme, an excessive amount of clampedtissue may cause binding and an incomplete firing.

When endoscopic surgical instruments fail, they are often returned tothe manufacturer, or other entity, for analysis of the failure. If thefailure resulted in a critical class of defect in the instrument, it isnecessary for the manufacturer to determine the cause of the failure anddetermine whether a design change is required. In that case, themanufacturer may spend many hundreds of man-hours analyzing a failedinstrument and attempting to reconstruct the conditions under which itfailed based only on the damage to the instrument. It can be expensiveand very challenging to analyze instrument failures in this way. Also,many of these analyses simply conclude that the failure was due toimproper use of the instrument.

Because the actuating force (i.e., the “force-to-fire”, or FTF)necessary to close the jaws and simultaneously perform the cutting andstapling operation may be considerable, a manually-powered cutting andstapling instrument such as that described above may not be utilizableby otherwise qualified users who are unable to generate the requiredFTF. Accordingly, powered cutting and stapling instruments have beendeveloped for decreasing the force-to-fire (FTF). Such instrumentstypically incorporate motors or other actuating mechanisms suitable forsupplementing or replacing user-generated force for performing thecutting and stapling operation.

Although powered instruments provide numerous advantages, it isdesirable to prevent inadvertent firing of the instrument under certainconditions. For example, firing the instrument without having a staplecartridge installed, or firing the instrument having an installed butspent staple cartridge, may result in cutting of tissue withoutsimultaneous stapling to minimize bleeding. Additionally, firing of theinstrument without proper closure of the jaw members may result in anunacceptable cutting and stapling operation and/or cause mechanicaldamage to the instrument. Similar consequences may result if the jawmembers are inadvertently opened while a cutting and stapling operationis in progress. It is particularly desirable that interlock features forpreventing such inadvertent firing and jaw manipulation be accomplishedin a reliable way that is not subject to an intervening malfunction.Moreover, for ease of manufacturing and assembly, it is furtherdesirable that the interlock features be accomplished with a minimumnumber of components.

Consequently, a significant need exists for electronic interlockfeatures for use in powered cutting and stapling instruments thatprevent inadvertent firing (i.e., cutting and stapling) and jawmanipulation during conditions such as those described above.

SUMMARY

In one general aspect, the present invention is directed to a surgicalinstrument. The surgical instrument has an end effector and a trigger incommunication with the end effector. The surgical instrument also has afirst sensor and an externally accessible memory device in communicationwith the first sensor. The first sensor has an output that represents afirst condition of either the trigger or the end effector. The memorydevice is configured to record the output of the first sensor. Invarious embodiments, memory device may include an output port and/or aremovable storage medium.

Also, in various embodiments, the output of the first sensor representsa condition of the end effector and the instrument further comprises asecond sensor with an output representing a condition of the trigger.The memory device is configured to record the output of the first sensorand the second sensor.

In another general aspect, the present invention is directed to a methodof recording the state of a surgical instrument. The method comprisesthe step of monitoring outputs of a plurality of sensors. The outputsrepresent conditions of the surgical instrument. The method alsocomprises the step of recording the outputs to a memory device when atleast one of the conditions of the surgical instrument changes. Invarious embodiments, the method may also comprise the step of providingthe recorded outputs of the plurality of sensors to an outside device.

DRAWINGS

Various embodiments of the present invention are described herein by wayof example in conjunction with the following figures, wherein

FIGS. 1 and 2 are perspective views of a surgical cutting and fasteninginstrument according to various embodiments of the present invention;

FIGS. 3-5 are exploded views of an end effector and shaft of theinstrument according to various embodiments of the present invention;

FIG. 6 is a side view of the end effector according to variousembodiments of the present invention;

FIG. 7 is an exploded view of the handle of the instrument according tovarious embodiments of the present invention;

FIGS. 8 and 9 are partial perspective views of the handle according tovarious embodiments of the present invention;

FIG. 10 is a side view of the handle according to various embodiments ofthe present invention;

FIGS. 10A and 10B illustrate a proportional sensor that may be usedaccording to various embodiments of the present invention;

FIG. 11 is a schematic diagram of a circuit that may be used in theinstrument according to various embodiments of the present invention;

FIG. 11A is a schematic diagram of another circuit that may be used inthe instrument according to various embodiments of the presentinvention;

FIGS. 12-13 are side views of the handle according to other embodimentsof the present invention;

FIGS. 14-22 illustrate different mechanisms for locking the closuretrigger according to various embodiments of the present invention;

FIGS. 23A-B show a universal joint (“u-joint”) that may be employed atthe articulation point of the instrument according to variousembodiments of the present invention;

FIGS. 24A-B shows a torsion cable that may be employed at thearticulation point of the instrument according to various embodiments ofthe present invention;

FIGS. 25-31 illustrate a surgical cutting and fastening instrument withpower assist according to another embodiment of the present invention;

FIGS. 32-36 illustrate a surgical cutting and fastening instrument withpower assist according to yet another embodiment of the presentinvention;

FIGS. 37-40 illustrate a surgical cutting and fastening instrument withtactile feedback to embodiments of the present invention;

FIG. 41 illustrates an exploded view of an end effector and shaft of theinstrument according to various embodiments of the present invention;

FIG. 42 illustrates a side view of the handle of a mechanicallyinstrument according to various embodiments of the present invention;

FIG. 43 illustrates an exploded view of the handle of the mechanicallyactuated instrument of FIG. 42;

FIG. 44 illustrates a block diagram of a recording system for recordingvarious conditions of the instrument according to various embodiments ofthe present invention;

FIGS. 45-46 illustrate cut away side views of a handle of the instrumentshowing various sensors according to various embodiments of the presentinvention;

FIG. 47 illustrates the end effector of the instrument showing varioussensors according to various embodiments of the present invention;

FIG. 48 illustrates a firing bar of the instrument including a sensoraccording to various embodiments of the present invention;

FIG. 49 illustrates a side view of the handle, end effector, and firingbar of the instrument showing a sensor according to various embodimentsof the present invention;

FIG. 50A illustrates an exploded view of the staple channel and portionsof a staple cartridge of the instrument showing various sensorsaccording to various embodiments of the present invention;

FIG. 50B illustrates a top down view of the staple channel of theinstrument showing various sensors according to various embodiments ofthe present invention;

FIGS. 51A-C illustrate mounting arrangements and configurations of thelockout sensor switches of an interlock circuit according to variousembodiments of the present invention;

FIGS. 52A and 52B illustrate a flow chart showing a method for operatingthe instrument according to various embodiments; and

FIG. 53 illustrates a memory chart showing exemplary recorded conditionsof the instrument according to various embodiments of the presentinvention.

FIGS. 54 and 55 illustrate another embodiment of the present inventionincluding an embodiment of an instrument wherein a retraction trigger issupported on the firing trigger for travel therewith.

FIG. 56 shows another embodiment of a current control circuit accordingto various embodiments of the present invention.

FIG. 57, 57A, 57B and 57C are schematic diagrams of other currentcontrol circuits according to various embodiments of the presentinvention.

FIGS. 58 and 59 show one embodiment of a way to lock the closure triggerto the pistol grip portion of the handle.

FIG. 60 is a schematic diagram of an electrical circuit of theinstrument according to various embodiments of the present inventionillustrating the use of the closure lock switch.

FIG. 61 shows one embodiment of a surgical instrument illustrating anexample position for a start switch.

FIGS. 62-65 shown end effector arrangements according to variousembodiments.

FIGS. 66-67 illustrate in general form, a distal end of a surgicalstapler of various embodiments of the present invention which includesan anvil, a cartridge body, and channel.

FIG. 68 illustrates the distal end of the surgical stapler of FIGS.66-67 when an indicator positioned thereon.

FIG. 69 illustrates the surgical stapler of FIGS. 66-67 with anindicator positioned on a handle thereof.

DETAILED DESCRIPTION

The owner of the subject application also owns the following U.S. PatentApplications that were filed on Jul. 29, 2010 and which are each hereinincorporated by reference in their respective entirety:

U.S. patent application Ser. No. 12/846,249, entitled MOTOR DRIVENSURGICAL FASTENER DEVICE WITH CUTTING MEMBER REVERSING MECHANISM, nowU.S. Pat. No. 8,453,907; and

U.S. patent application Ser. No. 12/846,237, entitled MOTOR DRIVENSURGICAL FASTENER DEVICE WITH MECHANISMS FOR ADJUSTING A TISSUE GAPWITHIN THE END EFFECTOR, now U.S. Pat. No. 8,444,036.

FIGS. 1 and 2 depict a surgical cutting and fastening instrument 10according to various embodiments of the present invention. Theillustrated embodiment is an endoscopic surgical instrument 10 and ingeneral, the embodiments of the instrument 10 described herein areendoscopic surgical cutting and fastening instruments. It should benoted, however, that according to other embodiments of the presentinvention, the instrument 10 may be a non-endoscopic surgical cuttinginstrument, such as a laproscopic instrument.

The surgical instrument 10 depicted in FIGS. 1 and 2 comprises a handle6, a shaft 8, and an articulating end effector 12 pivotally connected tothe shaft 8 at an articulation pivot 14. An articulation control 16 maybe provided adjacent to the handle 6 to effect rotation of the endeffector 12 about the articulation pivot 14. It will be appreciated thatvarious embodiments may include a non-pivoting end effector, andtherefore may not have an articulation pivot 14 or articulation control16. Also, in the illustrated embodiment, the end effector 12 isconfigured to act as an endocutter for clamping, severing and staplingtissue, although, in other embodiments, different types of end effectorsmay be used, such as end effectors for other types of surgical devices,such as graspers, cutters, staplers, clip appliers, access devices,drug/gene therapy devices, ultrasound, RF or laser devices, etc.

The handle 6 of the instrument 10 may include a closure trigger 18 and afiring trigger 20 for actuating the end effector 12. It will beappreciated that instruments having end effectors directed to differentsurgical tasks may have different numbers or types of triggers or othersuitable controls for operating the end effector 12. The end effector 12is shown separated from the handle 6 by a preferably elongate shaft 8.In one embodiment, a clinician or operator of the instrument 10 mayarticulate the end effector 12 relative to the shaft 8 by utilizing thearticulation control 16, as described in more detail in pending U.S.patent application Ser. No. 11/329,020, filed Jan. 10, 2006, entitledSURGICAL INSTRUMENT HAVING AN ARTICULATING END EFFECTOR, by Geoffrey C.Hueil et al., now U.S. Pat. No. 7,670,334 which is incorporated hereinby reference in its entirety.

The end effector 12 includes in this example, among other things, astaple channel 22 and a pivotally translatable clamping member, such asan anvil 24, which are maintained at a spacing that assures effectivestapling and severing of tissue clamped in the end effector 12. Thehandle 6 includes a pistol grip 26 toward which a closure trigger 18 ispivotally drawn by the clinician to cause clamping or closing of theanvil 24 towards the staple channel 22 of the end effector 12 to therebyclamp tissue positioned between the anvil 24 and channel 22. The firingtrigger 20 is farther outboard of the closure trigger 18. Once theclosure trigger 18 is locked in the closure position as furtherdescribed below, the firing trigger 20 may rotate slightly toward thepistol grip 26 so that it can be reached by the operator using one hand.Then the operator may pivotally draw the firing trigger 20 toward thepistol grip 26 to cause the stapling and severing of clamped tissue inthe end effector 12. In other embodiments, different types of clampingmembers besides the anvil 24 could be used, such as, for example, anopposing jaw, etc.

It will be appreciated that the terms “proximal” and “distal” are usedherein with reference to a clinician gripping the handle 6 of aninstrument 10. Thus, the end effector 12 is distal with respect to themore proximal handle 6. It will be further appreciated that, forconvenience and clarity, spatial terms such as “vertical” and“horizontal” are used herein with respect to the drawings. However,surgical instruments are used in many orientations and positions, andthese terms are not intended to be limiting and absolute.

The closure trigger 18 may be actuated first. Once the clinician issatisfied with the positioning of the end effector 12, the clinician maydraw back the closure trigger 18 to its fully closed, locked positionproximate to the pistol grip 26. The firing trigger 20 may then beactuated. The firing trigger 20 returns to the open position (shown inFIGS. 1 and 2) when the clinician removes pressure, as described morefully below. A release button on the handle 6, when depressed mayrelease the locked closure trigger 18. The release button may beimplemented in various forms such as, for example, release button 30shown in FIGS. 42-43, slide release button 160 shown in FIG. 14, and/orbutton 172 shown in FIG. 16.

FIGS. 3-6 show embodiments of a rotary-driven end effector 12 and shaft8 according to various embodiments. FIG. 3 is an exploded view of theend effector 12 according to various embodiments. As shown in theillustrated embodiment, the end effector 12 may include, in addition tothe previously-mentioned channel 22 and anvil 24, a cutting instrument32, a sled 33, a staple cartridge 34 that is removably seated in thechannel 22, and a helical screw shaft 36. The cutting instrument 32 maybe, for example, a knife. The anvil 24 may be pivotably opened andclosed at pivot pins 25 connected to the proximate end of the channel22. The anvil 24 may also include a tab 27 at its proximate end that isinserted into a component of the mechanical closure system (describedfurther below) to open and close the anvil 24. When the closure trigger18 is actuated, that is, drawn in by a user of the instrument 10, theanvil 24 may pivot about the pivot pins 25 into the clamped or closedposition. If clamping of the end effector 12 is satisfactory, theoperator may actuate the firing trigger 20, which, as explained in moredetail below, causes the knife 32 and sled 33 to travel longitudinallyalong the channel 22, thereby cutting tissue clamped within the endeffector 12. The movement of the sled 33 along the channel 22 causes thestaples (not shown) of the staple cartridge 34 to be driven through thesevered tissue and against the closed anvil 24, which turns the staplesto fasten the severed tissue. In various embodiments, the sled 33 may bean integral component of the cartridge 34. U.S. Pat. No. 6,978,921,entitled SURGICAL STAPLING INSTRUMENT INCORPORATING AN E-BEAM FIRINGMECHANISM to Shelton, IV et al., which is incorporated herein byreference in its entirety, provides more details about such two-strokecutting and fastening instruments. The sled 33 may be part of thecartridge 34, such that when the knife 32 retracts following the cuttingoperation, the sled 33 does not retract.

It should be noted that although the embodiments of the instrument 10described herein employ an end effector 12 that staples the severedtissue, in other embodiments different techniques for fastening orsealing the severed tissue may be used. For example, end effectors thatuse RF energy or adhesives to fasten the severed tissue may also beused. U.S. Pat. No. 5,709,680 entitled ELECTROSURGICAL HEMOSTATIC DEVICEto Yates et al., and U.S. Pat. No. 5,688,270 entitled ELECTROSURGICALHEMOSTATIC DEVICE WITH RECESSED AND/OR OFFSET ELECTRODES to Yates etal., which are incorporated herein by reference, disclose an endoscopiccutting instrument that uses RF energy to seal the severed tissue. U.S.patent application Ser. No. 11/267,811 to Jerome R. Morgan, et. al, nowU.S. Pat. No. 7,673,783 and U.S. patent application Ser. No. 11/267,383to Frederick E. Shelton, IV, et. al, now U.S. Pat. No. 7,607,557 whichare also incorporated herein by reference in their respective entiretiesdisclose cutting instruments that uses adhesives to fasten the severedtissue. Accordingly, although the description herein refers tocutting/stapling operations and the like below, it should be recognizedthat this is an exemplary embodiment and is not meant to be limiting.Other tissue fastening techniques may also be used.

FIGS. 4 and 5 are exploded views and FIG. 6 is a side view of the endeffector 12 and shaft 8 according to various embodiments. As shown inthe illustrated embodiment, the shaft 8 may include a proximate closuretube 40 and a distal closure tube 42 pivotably linked by a pivot link44. The distal closure tube 42 includes an opening 45 into which the tab27 on the anvil 24 is inserted in order to open and close the anvil 24,as further described below. Disposed inside the closure tubes 40, 42 maybe a proximate spine tube 46. Disposed inside the proximate spine tube46 may be a main rotational (or proximate) drive shaft 48 thatcommunicates with a secondary (or distal) drive shaft 50 via a bevelgear assembly 52. The secondary drive shaft 50 is connected to a drivegear 54 that engages a proximate drive gear 56 of the helical screwshaft 36. The vertical bevel gear 52 b may sit and pivot in an opening57 in the distal end of the proximate spine tube 46. A distal spine tube58 may be used to enclose the secondary drive shaft 50 and the drivegears 54, 56. Collectively, the main drive shaft 48, the secondary driveshaft 50, and the articulation assembly (e.g., the bevel gear assembly52 a-c) are sometimes referred to herein as the “main drive shaftassembly.”

A bearing 38, positioned at a distal end of the staple channel 22,receives the helical drive screw 36, allowing the helical drive screw 36to freely rotate with respect to the channel 22. The helical screw shaft36 may interface a threaded opening (not shown) of the knife 32 suchthat rotation of the shaft 36 causes the knife 32 to translate distallyor proximately (depending on the direction of the rotation) through thestaple channel 22. Accordingly, when the main drive shaft 48 is causedto rotate by actuation of the firing trigger 20 (as explained in moredetail below), the bevel gear assembly 52 a-c causes the secondary driveshaft 50 to rotate, which in turn, because of the engagement of thedrive gears 54, 56, causes the helical screw shaft 36 to rotate, whichcauses the knife driving member 32 to travel longitudinally along thechannel 22 to cut any tissue clamped within the end effector 12. Thesled 33 may be made of, for example, plastic, and may have a slopeddistal surface. As the sled 33 traverses the channel 22, the slopedforward surface may push up or drive the staples in the staple cartridgethrough the clamped tissue and against the anvil 24. The anvil 24 turnsthe staples, thereby stapling the severed tissue. When the knife 32 isretracted, the knife 32 and sled 33 may become disengaged, therebyleaving the sled 33 at the distal end of the channel 22.

As described above, because of the lack of user feedback for thecutting/stapling operation, there is a general lack of acceptance amongphysicians of motor-driven endocutters where the cutting/staplingoperation is actuated by merely pressing a button. In contrast,embodiments of the present invention provide a motor-driven endocutterwith user-feedback of the deployment, force and/or position of thecutting instrument 32 in end effector 12.

FIGS. 7-10 illustrate an exemplary embodiment of a motor-drivenendocutter, and in particular the handle thereof, that providesuser-feedback regarding the deployment and loading force of the cuttinginstrument 32 in the end effector 12. In addition, the embodiment mayuse power provided by the user in retracting the firing trigger 20 topower the device (a so-called “power assist” mode). The embodiment maybe used with the rotary driven end effector 12 and shaft 8 embodimentsdescribed above. As shown in the illustrated embodiment, the handle 6includes exterior lower side pieces 59, 60 and exterior upper sidepieces 61, 62 that fit together to form, in general, the exterior of thehandle 6. A battery 64, such as a Li ion battery, may be provided in thepistol grip portion 26 of the handle 6. The battery 64 powers a motor 65disposed in an upper portion of the pistol grip portion 26 of the handle6. According to various embodiments, the motor 65 may be a DC brusheddriving motor having a maximum rotation of, approximately, 5000 RPM. Themotor 65 may drive a 90° bevel gear assembly 66 comprising a first bevelgear 68 and a second bevel gear 70. The bevel gear assembly 66 may drivea planetary gear assembly 72. The planetary gear assembly 72 may includea pinion gear 74 connected to a drive shaft 76. The pinion gear 74 maydrive a mating ring gear 78 that drives a helical gear drum 80 via adrive shaft 82. A ring 84 may be threaded on the helical gear drum 80.Thus, when the motor 65 rotates, the ring 84 is caused to travel alongthe helical gear drum 80 by means of the interposed bevel gear assembly66, planetary gear assembly 72 and ring gear 78.

The handle 6 may also include a run motor sensor 110 (see FIG. 10) incommunication with the firing trigger 20 to detect when the firingtrigger 20 has been drawn in (or “closed”) toward the pistol gripportion 26 of the handle 6 by the operator to thereby actuate thecutting/stapling operation by the end effector 12. The sensor 110 may bea proportional sensor such as, for example, a rheostat or variableresistor. When the firing trigger 20 is drawn in, the sensor 110 detectsthe movement, and sends an electrical signal indicative of the voltage(or power) to be supplied to the motor 65. When the sensor 110 is avariable resistor or the like, the rotation of the motor 65 may begenerally proportional to the amount of movement of the firing trigger20. That is, if the operator only draws or closes the firing trigger 20in a little bit, the rotation of the motor 65 is relatively low. Whenthe firing trigger 20 is fully drawn in (or in the fully closedposition), the rotation of the motor 65 is at its maximum. In otherwords, the harder the user pulls on the firing trigger 20, the morevoltage is applied to the motor 65, causing greater rates of rotation.

The handle 6 may include a middle handle piece 104 adjacent to the upperportion of the firing trigger 20. The handle 6 also may comprise a biasspring 112 connected between posts on the middle handle piece 104 andthe firing trigger 20. The bias spring 112 may bias the firing trigger20 to its fully open position. In that way, when the operator releasesthe firing trigger 20, the bias spring 112 will pull the firing trigger20 to its open position, thereby removing actuation of the sensor 110,thereby stopping rotation of the motor 65. Moreover, by virtue of thebias spring 112, any time a user closes the firing trigger 20, the userwill experience resistance to the closing operation, thereby providingthe user with feedback as to the amount of rotation exerted by the motor65. Further, the operator could stop retracting the firing trigger 20 tothereby remove force from the sensor 100, to thereby stop the motor 65.As such, the user may stop the deployment of the end effector 12,thereby providing a measure of control of the cutting/fasteningoperation to the operator.

The distal end of the helical gear drum 80 includes a distal drive shaft120 that drives a ring gear 122, which mates with a pinion gear 124. Thepinion gear 124 is connected to the main drive shaft 48 of the maindrive shaft assembly. In that way, rotation of the motor 65 causes themain drive shaft assembly to rotate, which causes actuation of the endeffector 12, as described above.

The ring 84 threaded on the helical gear drum 80 may include a post 86that is disposed within a slot 88 of a slotted arm 90. The slotted arm90 has an opening 92 its opposite end 94 that receives a pivot pin 96that is connected between the handle exterior side pieces 59, 60. Thepivot pin 96 is also disposed through an opening 100 in the firingtrigger 20 and an opening 102 in the middle handle piece 104.

In addition, the handle 6 may include a reverse motor sensor (orend-of-stroke sensor) 130 and a stop motor (or beginning-of-stroke)sensor 142. In various embodiments, the reverse motor sensor 130 may bea limit switch located at the distal end of the helical gear drum 80such that the ring 84 threaded on the helical gear drum 80 contacts andtrips the reverse motor sensor 130 when the ring 84 reaches the distalend of the helical gear drum 80. The reverse motor sensor 130, whenactivated, sends a signal to the motor 65 to reverse its rotationdirection, thereby withdrawing the knife 32 of the end effector 12following the cutting operation.

The stop motor sensor 142 may be, for example, a normally-closed limitswitch. In various embodiments, it may be located at the proximate endof the helical gear drum 80 so that the ring 84 trips the switch 142when the ring 84 reaches the proximate end of the helical gear drum 80.

In operation, when an operator of the instrument 10 pulls back thefiring trigger 20, the sensor 110 detects the deployment of the firingtrigger 20 and sends a signal to the motor 65 to cause forward rotationof the motor 65, for example, at a rate proportional to how hard theoperator pulls back the firing trigger 20. The forward rotation of themotor 65 in turn causes the ring gear 78 at the distal end of theplanetary gear assembly 72 to rotate, thereby causing the helical geardrum 80 to rotate, causing the ring 84 threaded on the helical gear drum80 to travel distally along the helical gear drum 80. The rotation ofthe helical gear drum 80 also drives the main drive shaft assembly asdescribed above, which in turn causes deployment of the knife 32 in theend effector 12. That is, the knife 32 and sled 33 are caused totraverse the channel 22 longitudinally, thereby cutting tissue clampedin the end effector 12. Also, the stapling operation of the end effector12 is caused to happen in embodiments where a stapling-type end effector12 is used.

By the time the cutting/stapling operation of the end effector 12 iscomplete, the ring 84 on the helical gear drum 80 will have reached thedistal end of the helical gear drum 80, thereby causing the reversemotor sensor 130 to be tripped, which sends a signal to the motor 65 tocause the motor 65 to reverse its rotation. This in turn causes theknife 32 to retract, and also causes the ring 84 on the helical geardrum 80 to move back to the proximate end of the helical gear drum 80.

The middle handle piece 104 includes a backside shoulder 106 thatengages the slotted arm 90 as best shown in FIGS. 8 and 9. The middlehandle piece 104 also has a forward motion stop 107 that engages thefiring trigger 20. The movement of the slotted arm 90 is controlled, asexplained above, by rotation of the motor 65. When the slotted arm 90rotates counter clockwise as the ring 84 travels from the proximate endof the helical gear drum 80 to the distal end, the middle handle piece104 will be free to rotate counter clockwise. Thus, as the user draws inthe firing trigger 20, the firing trigger 20 will engage the forwardmotion stop 107 of the middle handle piece 104, causing the middlehandle piece 104 to rotate counter clockwise. Due to the backsideshoulder 106 engaging the slotted arm 90, however, the middle handlepiece 104 will only be able to rotate counter clockwise as far as theslotted arm 90 permits. In that way, if the motor 65 should stoprotating for some reason, the slotted arm 90 will stop rotating, and theuser will not be able to further draw in the firing trigger 20 becausethe middle handle piece 104 will not be free to rotate counter clockwisedue to the slotted arm 90.

FIGS. 10A and 10B illustrate two states of a variable sensor that may beused as the run motor sensor 110 according to various embodiments of thepresent invention. The sensor 110 may include a face portion 280, afirst electrode (A) 282, a second electrode (B) 284, and a compressibledielectric material 286 between the electrodes 282, 284, such as, forexample, an electroactive polymer (EAP). The sensor 110 may bepositioned such that the face portion 280 contacts the firing trigger 20when retracted. Accordingly, when the firing trigger 20 is retracted,the dielectric material 286 is compressed, as shown in FIG. 10B, suchthat the electrodes 282, 284 are closer together. Since the distance “b”between the electrodes 282, 284 is directly related to the impedancebetween the electrodes 282, 284, the greater the distance the moreimpedance, and the closer the distance the less impedance. In that way,the amount that the dielectric 286 is compressed due to retraction ofthe firing trigger 20 is proportional to the impedance between theelectrodes 282, 284, which can be used to proportionally control themotor 65.

Components of an exemplary closure system for closing (or clamping) theanvil 24 of the end effector 12 by retracting the closure trigger 18 arealso shown in FIGS. 7-10. In the illustrated embodiment, the closuresystem includes a yoke 250 connected to the closure trigger 18 by apivot pin 251 inserted through aligned openings in both the closuretrigger 18 and the yoke 250. A pivot pin 252, about which the closuretrigger 18 pivots, is inserted through another opening in the closuretrigger 18 which is offset from where the pin 251 is inserted throughthe closure trigger 18. Thus, retraction of the closure trigger 18causes the upper part of the closure trigger 18, to which the yoke 250is attached via the pin 251, to rotate counterclockwise. The distal endof the yoke 250 is connected, via a pin 254, to a first closure bracket256. The first closure bracket 256 connects to a second closure bracket258. Collectively, the closure brackets 256, 258 define an opening inwhich the proximate end of the proximate closure tube 40 (see FIG. 4) isseated and held such that longitudinal movement of the closure brackets256, 258 causes longitudinal motion by the proximate closure tube 40.The instrument 10 also includes a closure rod 260 disposed inside theproximate closure tube 40. The closure rod 260 may include a window 261into which a post 263 on one of the handle exterior pieces, such asexterior lower side piece 59 in the illustrated embodiment, is disposedto fixedly connect the closure rod 260 to the handle 6. In that way, theproximate closure tube 40 is capable of moving longitudinally relativeto the closure rod 260. The closure rod 260 may also include a distalcollar 267 that fits into a cavity 269 in proximate spine tube 46 and isretained therein by a cap 271 (see FIG. 4).

In operation, when the yoke 250 rotates due to retraction of the closuretrigger 18, the closure brackets 256, 258 cause the proximate closuretube 40 to move distally (i.e., away from the handle end of theinstrument 10), which causes the distal closure tube 42 to movedistally, which causes the anvil 24 to rotate about the pivot pins 25into the clamped or closed position. When the closure trigger 18 isunlocked from the locked position, the proximate closure tube 40 iscaused to slide proximately, which causes the distal closure tube 42 toslide proximately, which, by virtue of the tab 27 being inserted in thewindow 45 of the distal closure tube 42, causes the anvil 24 to pivotabout the pivot pins 25 into the open or unclamped position. In thatway, by retracting and locking the closure trigger 18, an operator mayclamp tissue between the anvil 24 and channel 22, and may unclamp thetissue following the cutting/stapling operation by unlocking the closuretrigger 20 from the locked position.

FIG. 11 is a schematic diagram of an electrical circuit of theinstrument 10 according to various embodiments of the present invention.When an operator initially pulls in the firing trigger 20 after lockingthe closure trigger 18, the sensor 110 is activated, allowing current toflow therethrough. If the normally-open reverse motor sensor switch 130is open (meaning the end of the end effector stroke has not beenreached), current will flow to a single pole, double throw relay 132.Since the reverse motor sensor switch 130 is not closed, the inductor134 of the relay 132 will not be energized, so the relay 132 will be inits non-energized state. The circuit also includes a cartridge lockoutsensor 136. If the end effector 12 includes a staple cartridge 34, thesensor 136 will be in the closed state, allowing current to flow.Otherwise, if the end effector 12 does not include a staple cartridge34, the sensor 136 will be open, thereby preventing the battery 64 frompowering the motor 65.

When the staple cartridge 34 is present, the sensor 136 is closed, whichenergizes a single pole, single throw relay 138. When the relay 138 isenergized, current flows through the relay 136, through the variableresistor sensor 110, and to the motor 65 via a double pole, double throwrelay 140, thereby powering the motor 65 and allowing it to rotate inthe forward direction.

When the end effector 12 reaches the end of its stroke, the reversemotor sensor 130 will be activated, thereby closing the switch 130 andenergizing the relay 134. This causes the relay 134 to assume itsenergized state (not shown in FIG. 13), which causes current to bypassthe cartridge lockout sensor 136 and variable resistor 110, and insteadcauses current to flow to both the normally-closed double pole, doublethrow relay 140 and back to the motor 65, but in a manner, via the relay140, that causes the motor 65 to reverse its rotational direction.

Because the stop motor sensor switch 142 is normally-closed, currentwill flow back to the relay 134 to keep it closed until the switch 142opens. When the knife 32 is fully retracted, the stop motor sensorswitch 142 is activated, causing the switch 142 to open, therebyremoving power from the motor 65.

In other embodiments, rather than a proportional-type sensor 110, anon-off type sensor could be used. In such embodiments, the rate ofrotation of the motor 65 would not be proportional to the force appliedby the operator. Rather, the motor 65 would generally rotate at aconstant rate. But the operator would still experience force feedbackbecause the firing trigger 20 is geared into the gear drive train.

FIG. 11A is a schematic diagram of another electrical circuit of theinstrument 10 according to various embodiments of the present invention.This electrical circuit includes lockout sensor switches 136 a-dcollectively defining an interlock circuit 137 through which currentfrom the relay 132, when de-energized, must pass in order for electricaloperation of the motor 65 to be initiated. Each lockout sensor switch136 a-d is configured to maintain an open (i.e., non-conductive) switchstate or a closed (i.e., conductive) switch state responsive to thepresence or absence, respectively, of a corresponding condition. Any ofthe corresponding conditions, if present when the instrument 10 isfired, may result in an unsatisfactory cutting and stapling operationand/or damage to the instrument 10. Conditions to which the lockoutsensor switches 136 a-d may respond include, for example, the absence ofthe staple cartridge 34 in the channel 22, the presence of a spent(e.g., previously fired) staple cartridge 34 in the channel 22, and anopen (or otherwise insufficiently closed) position of the anvil 24 withrespect to the channel 22. Other conditions to which the lockout sensorswitches 136 a-d may respond, such as component wear, may be inferredbased upon an accumulated number of firing operations produced by theinstrument 10. Accordingly, if any of these conditions exists, thecorresponding lockout sensor switches 136 a-d maintain an open switchstate, thus preventing passage of the current necessary to initiateoperation of the motor 65. Passage of current by the lockout sensors 136a-d is allowed only after all of the conditions have been remedied. Itwill be appreciated that the above-described conditions are provided byway of example only, and that additional lockout sensor switches forresponding to other conditions detrimental to operation of theinstrument 10 may be provided. It will similarly be appreciated that forembodiments in which one or more of the above-described conditions maynot exist or are of no concern, the number of lockout sensor switchesmay be fewer than that depicted.

As shown in FIG. 11A, the lockout sensor switch 136 a may be implementedusing a normally-open switch configuration such that a closed switchstate is maintained when the staple cartridge 34 is in a positioncorresponding to its proper receipt by the channel 22. When the staplecartridge 34 is not installed in the channel 22, or is installedimproperly (e.g., mis-aligned), the lockout sensor switch 136 amaintains an open switch state.

Lockout sensor switch 136 b may be implemented using a normally-openswitch configuration such that a closed switch state is maintained onlywhen an unspent staple cartridge 34 (i.e., a staple cartridge 34 havinga sled 33 in the unfired position) is present in the channel 22. Thepresence of a spent staple cartridge 34 in the channel 22 causes thelockout sensor switch 136 b to maintain an open switch state.

Lockout sensor switch 136 c may be implemented using a normally-openswitch configuration such that a closed switch state is maintained whenthe anvil 24 is in a closed position with respect to the channel 22. Asdiscussed in further detail below, the lockout sensor switch 136 c maybe controlled in accordance with a time delay feature wherein a closedswitch state is maintained only after the anvil 24 is in the closedposition for a pre-determined period of time.

Lockout sensor switch 136 d may be implemented using a normally-closedswitch configuration such that a closed switch state is maintained onlywhen an accumulated number of firings produced by the instrument 10 isless than a pre-determined number. As discussed in further detail below,the lockout sensor switch 136 d may be in communication with a counter304 configured for maintaining a count representative of the accumulatednumber of firing operations performed by the instrument, comparing thecount to the pre-determined number, and controlling the switch state ofthe lockout sensor switch 136 d based upon the comparison.

According to various embodiments, the interlock circuit 137 may compriseone or more indicators visible to the user of the instrument 10 fordisplaying a status of at least one of the lockout sensor switches 136a-c. As shown in FIG. 11A, for example, each lockout sensor switch 136a-d may have a green LED 139 a and a red LED 139 b associated therewith.The interlock circuit 137 may be configured such that the LEDs 139 a,bare energized when the corresponding lockout sensor switch 136 a-d ismaintained in the closed and open switch states, respectively. It willbe appreciated that the lockout sensor switches 136 a-d may comprise oneor more auxiliary switch contacts (not shown) having a switchconfiguration suitable for operating the LEDs 139 a,b in the mannerdescribed above.

FIGS. 50A-51C illustrate mounting arrangements and configurations of thelockout sensor switches 136 a-d of the interlock circuit 137 accordingto various embodiments of the present invention. As shown in FIG. 50A,the lockout sensor switch 136 a may comprise a first switch contact 288a and a second switch contact 288 b disposed upon an inner wall of thechannel 22 and electrically isolated therefrom. The respective positionsof the first and second switch contacts 288 a,b are such that when thestaple cartridge 34 is in a position corresponding to its proper receiptby the channel 22, a conductive or semi-conductive portion 290 of thestaple cartridge 34 (exemplified as a metal tray portion of the staplecartridge 34) contacts the first and second switch contacts 288 a,b toestablish a conductive path therebetween.

As best seen in FIG. 50B, each switch contact 288 a,b may comprise arounded profile for minimizing mechanical resistance to the staplecartridge 34 when received by the channel 22 and for enablingaffirmative electrical contact with the conductive portion 290 thereof.The conductive portion 290 thus operates to maintain the lockout sensorswitch 136 a in a closed switch state. Although the switch contacts 288a,b are shown adjacently positioned on a sidewall portion of the channel22, it will be appreciated that each switch contact 288 a,b maygenerally be located at any location within the channel 22 wheresuitable electrical contact with the conductive member 290 is possible.It will further be appreciated that the lockout sensor switch 136 a mayalternatively be implemented using a conventional contact-actuated limitswitch. According to such embodiments, the limit switch may bepositioned such that staple cartridge 34, when received by the channel22, mechanically actuates the limit switch such that a closed switchstate is maintained. It will further be appreciated that the lockoutsensor switch 136 a may also be implemented using a conventionalnon-contact actuated limit switch, such as, for example, a magnetic reedlimit switch or a Hall effect proximity switch. According to suchembodiments, the staple cartridge 34 may comprise a magnet suitable forcausing the lockout sensor switch 136 a to maintain a closed switchstate when the staple cartridge 34 is installed.

As best seen in FIG. 50B, the lockout sensor switch 136 b may be mountedon an interior bottom surface of the channel 22. According to variousembodiments and as shown, the lockout sensor switch 136 b may beimplemented using a contact-actuated limit switch of a conventionaldesign that is suitable for detecting linear movement. Orientation ofthe lockout sensor switch 136 b may be such that an actuated portionthereof extends upwardly from the bottom interior surface of the channel22. The position of the lockout sensor switch 136 b on the bottomsurface of the channel 22 is such that when an unspent staple cartridge34 is installed, a bottom portion of the sled 33 mechanically actuatesthe lockout sensor switch 136 b and causes a closed switch state to bemaintained thereby. Accordingly, the presence of an unspent staplecartridge 34 (i.e., a staple cartridge having a sled 33 in the unfiredposition) enables the passage of current through the lockout sensorswitch 136 b. It will be appreciated the lockout sensor switch 136 b mayinstead be implemented using a non-contact actuated switch (e.g., amagnetic reed limit switch or a Hall effect proximity switch). For suchimplementations, the sled 33 may comprise a magnetized portion, forexample, that actuates the lockout sensor switch 136 b when the sled 33is present in the un-fired position.

As shown in FIG. 51A, the lockout sensor switch 136 c is positionedadjacent a distal end of one of the pivot recesses 296 defined by theproximal end of the channel 22 for engaging a corresponding pivot point25 of the anvil 24. According to various embodiments and as shown, thelockout sensor switch 136 c may be implemented using a contact-actuatedlimit switch of a conventional design that is suitable for detectinglinear movement. It will be appreciated, however, that anon-contact-actuated limit switch may be used instead. Orientation ofthe lockout sensor switch 136 c may be such that an actuated portionthereof extends slightly over the distal end of the corresponding pivotrecess 296. When the anvil 24 is in an open position with respect to thechannel 22 (as shown in FIG. 51A), the pivot point 25 is positioned atthe proximal end of the pivot recess 296. Closure of the anvil 24 causesthe pivot point 25 to move to the distal end of the pivot recess 296.The resulting contact of the pivot point 25 with the actuated portion ofthe lockout sensor switch 136 c causes the lockout sensor switch 136 cto maintain a closed switch state, thus enabling the passage of currenttherethrough.

According to other embodiments and as shown in FIG. 51B, the lockoutsensor switch 136 c may instead be configured to maintain a closedswitch state responsive to an electrical signal. The electrical signalmay be, for example, an analog signal generated by a force sensor 298disposed on a bottom inner surface of the channel 22 that represents amagnitude of the clamping force applied by the anvil 24. The closedposition of the anvil 24 may thus be inferred if the analog signal issufficiently large in magnitude. Accordingly, the analog signal may bereceived by a comparator circuit 141 configured to determine if themagnitude exceeds a pre-determined threshold stored therein. If thethreshold is exceeded, indicating closure of the anvil 24, thecomparator circuit 141 causes the lockout sensor switch 136 c tomaintain a closed switch state, thus enabling the passage of currenttherethrough. If the magnitude of the analog signal is less than thepre-determined threshold, indicating that the anvil 24 is notsufficiently closed, the comparator circuit 141 causes the lockoutsensor switch 136 c to maintain an open switch state, thus preventingthe passage of current therethrough. Although shown separately, it willbe appreciated that the comparator circuit 141 may be integral with thelockout sensor switch 136 c so as to form a common device. It willfurther be appreciated that the pre-defined threshold stored by thecomparator circuit 141 may be adjusted as necessary to reflect the forceindicative of closure of the anvil 24 for different cutting and staplingoperations.

In certain instances, it may be necessary or otherwise desirable todelay commencement of a firing operation for a period of time subsequentto closure of the anvil 24. For example, the introduction of a delaybetween the clamping and firing operations may serve to improve thestabilization of clamped tissue. Accordingly, with reference to FIG.51C, embodiments of the present invention may comprise a timer 300having a pre-set time delay (e.g., 12 seconds) and configured forcontrolling the switch state of the lockout sensor switch 136 c inaccordance with a time-based position of the anvil 24. Although shownseparately, it will be appreciated that the timer 300 may be integralwith the lockout sensor switch 136 c so as to form a common device(e.g., an on-delay timer). Preferably, the timer 300 is implemented asan electronic device, although it will be appreciated that a mechanicaltimer may be used instead. A normally-open limit switch 302 configuredin a manner identical to that of FIG. 51A may be connected to the timer300 such that timing is initiated when the anvil 24 is in a closedposition with respect to the channel 22. Upon expiration of the pre-settime delay, the timer 300 causes the lockout sensor switch 136 c tomaintain a closed switch state, thus enabling the passage of currenttherethrough. The timer 300 may be reset in response to the transitionof the limit switch 302 to an open switch state (i.e., when the anvil 24is in the open position). It will be appreciated that the pre-set timedelay of the timer 300 may be selectively adjusted (e.g., using anintegral potentiometer adjustment) as required.

Referring again to FIG. 11A, the electrical circuit may comprise acounter 304 configured to maintain a count representative of theaccumulated number of firing operations performed by the instrument 10and, based on the count, to control the switch state of the lockoutsensor switch 136 d. Although shown separately, it will be appreciatedthat counter 304 may be integral with the lockout sensor switch 136 d soas to form a common device. Preferably, the counter 304 is implementedas an electronic device having an input for incrementing the maintainedcount based upon the transition of a discrete electrical signal providedthereto. It will be appreciated that a mechanical counter configured formaintaining the count based upon a mechanical input (e.g., retraction ofthe firing trigger 20) may be used instead. When implemented as anelectronic device, any discrete signal present in the electrical circuitthat transitions once for each firing operation may be utilized for thecounter 304 input. As shown in FIG. 11A, for example, the discreteelectrical signal resulting from actuation of the end-of-stroke sensor130 may be utilized. The counter 304 may control the switch state oflockout sensor switch 136 d such that a closed switch state ismaintained when the maintained count is less than a pre-determinednumber stored within the counter 304.

When the maintained count is equal to the pre-determined number, thecounter 304 causes the lockout sensor switch 136 d to maintain an openswitch state, thus preventing the passage of current therethrough. Itwill be appreciated that the pre-determined number stored by the counter304 may be selectively adjusted as required. According to variousembodiments, the counter 304 may be in communication with a display 305,such as an LCD display, integral to the instrument 10 for indicating toa user either the maintained count or the difference between thepre-determined number and the maintained count.

When the lockout sensor switches 136 a-d collectively maintain a closedswitch state, a single pole, single throw relay 138 is energized. Whenthe relay 138 is energized, current flows through the relay 138, throughthe variable resistor sensor 110, and to the motor 65 via a double pole,double throw relay 140, thereby powering the motor 65 and allowing it torotate in the forward direction. Because the output of the relay 138,once energized, maintains the relay 138 in an energized state untilrelay 132 is energized, the interlock circuit 137 will not function toprevent operation of the motor 165 once initiated, even if one or moreof the interlock sensor switches 136 a-d subsequently maintains an openswitch state. In other embodiments, however, it may be necessary orotherwise desirable to connect the interlock circuit 137 and the relay138 such that one or more the lockout sensor switches 136 a-d mustmaintain a closed switch state in order to sustain operation of themotor 165 once initiated.

Rotation of the motor in the forward direction causes the ring 84 tomove distally and thereby de-actuate the stop motor sensor switch 142.Because the switch 142 is normally-closed, solenoid 306 is energized.The solenoid 306 may be a conventional push-type solenoid that, whenenergized, causes a plunger (not shown) to be axially extended. Asdiscussed below in connection with FIGS. 14-22, extension of the plungermay operate to retain the closure trigger 18 in the retracted position,thus preventing the anvil 24 from opening while a firing operation is inprogress (i.e., while the switch 142 is not actuated). Uponde-energization of the solenoid 306, the plunger is retracted such thatmanual release of the closure trigger 18 is possible.

When the end effector 12 reaches the end of its stroke, the reversemotor sensor 130 will be activated, thereby closing the switch 130 andenergizing the relay 132. This causes the relay 132 to assume itsenergized state, which causes current to bypass the interlock circuit137 and variable resistor 110, and instead causes current to flow toboth the normally-closed double pole, double throw relay 140 and back tothe motor 65, but in a manner, via the relay 140, that causes the motor65 to reverse its rotational direction.

Because the stop motor sensor switch 142 is normally-closed, currentwill flow back to the relay 132 to keep it energized until the switch142 opens. When the knife 32 is fully retracted, the stop motor sensorswitch 142 is activated, causing the switch 142 to open, therebyremoving power from the motor 65 and de-energizing the solenoid 306.

In other embodiments, rather than a proportional-type sensor 110, anon-off type sensor could be used. In such embodiments, the rate ofrotation of the motor 65 would not be proportional to the force appliedby the operator. Rather, the motor 65 would generally rotate at aconstant rate. But the operator would still experience force feedbackbecause the firing trigger 20 is geared into the gear drive train.

FIG. 12 is a side-view of the handle 6 of a power-assist motorizedendocutter according to another embodiment. The embodiment of FIG. 12 issimilar to that of FIGS. 7-10 except that in the embodiment of FIG. 12,there is no slotted arm connected to the ring 84 threaded on the helicalgear drum 80. Instead, in the embodiment of FIG. 12, the ring 84includes a sensor portion 114 that moves with the ring 84 as the ring 84advances down (and back) on the helical gear drum 80. The sensor portion114 includes a notch 116. The reverse motor sensor 130 may be located atthe distal end of the notch 116 and the stop motor sensor 142 may belocated at the proximate end of the notch 116. As the ring 84 moves downthe helical gear drum 80 (and back), the sensor portion 114 moves withit. Further, as shown in FIG. 12, the middle piece 104 may have an arm118 that extends into the notch 12.

In operation, as an operator of the instrument 10 retracts in the firingtrigger 20 toward the pistol grip 26, the run motor sensor 110 detectsthe motion and sends a signal to power the motor 65, which causes, amongother things, the helical gear drum 80 to rotate. As the helical geardrum 80 rotates, the ring 84 threaded on the helical gear drum 80advances (or retracts, depending on the rotation). Also, due to thepulling in of the firing trigger 20, the middle piece 104 is caused torotate counter clockwise with the firing trigger 20 due to the forwardmotion stop 107 that engages the firing trigger 20. The counterclockwise rotation of the middle piece 104 cause the arm 118 to rotatecounter clockwise with the sensor portion 114 of the ring 84 such thatthe arm 118 stays disposed in the notch 116. When the ring 84 reachesthe distal end of the helical gear drum 80, the arm 118 will contact andthereby trip the reverse motor sensor 130. Similarly, when the ring 84reaches the proximate end of the helical gear drum 80, the arm willcontact and thereby trip the stop motor sensor 142. Such actions mayreverse and stop the motor 65, respectively as described above.

FIG. 13 is a side-view of the handle 6 of a power-assist motorizedendocutter according to another embodiment. The embodiment of FIG. 13 issimilar to that of FIGS. 7-10 except that in the embodiment of FIG. 13,there is no slot in the arm 90. Instead, the ring 84 threaded on thehelical gear drum 80 includes a vertical channel 126. Instead of a slot,the arm 90 includes a post 128 that is disposed in the channel 126. Asthe helical gear drum 80 rotates, the ring 84 threaded on the helicalgear drum 80 advances (or retracts, depending on the rotation). The arm90 rotates counter clockwise as the ring 84 advances due to the post 128being disposed in the channel 126, as shown in FIG. 13.

As mentioned above, in using a two-stroke motorized instrument, theoperator first pulls back and locks the closure trigger 18. FIGS. 14 and15 show one embodiment of a way to lock the closure trigger 18 to thepistol grip portion 26 of the handle 6. In the illustrated embodiment,the pistol grip portion 26 includes a hook 150 that is biased to rotateCCW about a pivot point 151 by a torsion spring 152. Also, the closuretrigger 18 includes a closure bar 154. As the operator draws in theclosure trigger 18, the closure bar 154 engages a sloped portion 156 ofthe hook 150, thereby rotating the hook 150 upward (or CW in FIGS.14-15) until the closure bar 154 completely passes the sloped portion156 into a recessed notch 158 of the hook 150, which locks the closuretrigger 18 in place. The operator may release the closure trigger 18 bypushing down on a slide button release 160 on the back or opposite sideof the pistol grip portion 26. Pushing down the slide button release 160rotates the hook 150 CW such that the closure bar 154 is released fromthe recessed notch 158. In order to prevent the anvil 24 frominadvertently being opened while a firing operation is in progress, thesolenoid 306 may be positioned within the pistol grip 26 such that theplunger 308 of the solenoid 306, when energized, is received into acorresponding opening 163 of the slide button release 160. Accordingly,the slide button release 160 is locked in place such that manipulationof the slide button release 160 is prevented until the plunger 308 isretracted from the opening 163 at the conclusion of the firingoperation.

FIG. 16 shows another closure trigger locking mechanism according tovarious embodiments. In the embodiment of FIG. 16, the closure trigger18 includes a wedge 160 having an arrow-head portion 161. The arrow-headportion 161 is biased downward (or clockwise) by a leaf spring 162. Thewedge 160 and leaf spring 162 may be made from, for example, moldedplastic. When the closure trigger 18 is retracted, the arrow-headportion 161 is inserted through an opening 164 in the pistol gripportion 26 of the handle 6. A lower chamfered surface 166 of thearrow-head portion 161 engages a lower sidewall 168 of the opening 164,forcing the arrow-head portion 161 to rotate counter clockwise.Eventually the lower chamfered surface 166 fully passes the lowersidewall 168, removing the counter clockwise force on the arrow-headportion 161, causing the lower sidewall 168 to slip into a lockedposition in a notch 170 behind the arrow-head portion 161.

To unlock the closure trigger 18, a user presses down on a button 172 onthe opposite side of the closure trigger 18, causing the arrow-headportion 161 to rotate CCW and allowing the arrow-head portion 161 toslide out of the opening 164. In order to prevent the anvil 24 frominadvertently being opened while a firing operation is in progress, thesolenoid 306 may be positioned within the pistol grip 26 such that theplunger 308 of the solenoid 306, when energized, is received into acorresponding opening 173 defined by the arrow-head portion 161. Whenreceived into the opening 173, the plunger 308 operates to prevent CCWrotation of the arrow-head portion 161. Accordingly, inadvertentmanipulation of the button 172 by the user is prevented by the useruntil the plunger 308 is retracted from the opening 173 at theconclusion of the firing operation.

FIGS. 17-22 show a closure trigger locking mechanism according toanother embodiment. As shown in this embodiment, the closure trigger 18includes a flexible longitudinal arm 176 that includes a lateral pin 178extending therefrom. The arm 176 and pin 178 may be made from moldedplastic, for example. The pistol grip portion 26 of the handle 6includes an opening 180 with a laterally extending wedge 182 disposedtherein. When the closure trigger 18 is retracted, the pin 178 engagesthe wedge 182, and the pin 178 is forced downward (i.e., the arm 176 isrotated clockwise) by the lower surface 184 of the wedge 182, as shownin FIGS. 17 and 18. When the pin 178 fully passes the lower surface 184,the clockwise force on the arm 176 is removed, and the pin 178 isrotated counter clockwise such that the pin 178 comes to rest in a notch186 behind the wedge 182, as shown in FIG. 19, thereby locking theclosure trigger 18. The pin 178 is further held in place in the lockedposition by a flexible stop 188 extending from the wedge 184.

To unlock the closure trigger 18, the operator may further squeeze theclosure trigger 18, causing the pin 178 to engage a sloped backwall 190of the opening 180, forcing the pin 178 upward past the flexible stop188, as shown in FIGS. 20 and 21. The pin 178 is then free to travel outan upper channel 192 in the opening 180 such that the closure trigger 18is no longer locked to the pistol grip portion 26, as shown in FIG. 22.In order to prevent the anvil 24 from inadvertently being opened while afiring operation is in progress, the solenoid 306 may be positionedwithin the pistol grip 26 such that the plunger 308 of the solenoid 306,when energized, is received into the upper channel 192. When receivedinto the upper channel 192, the plunger 308 operates to prevent passageof the pin 178 therethrough. Accordingly, unlocking the closure trigger18 is prevented until the plunger 308 is retracted from the upperchannel 192 at the conclusion of the firing operation.

FIGS. 23A-B show a universal joint (“u-joint”) 195. The second piece195-2 of the u-joint 195 rotates in a horizontal plane in which thefirst piece 195-1 lies. FIG. 23A shows the u-joint 195 in a linear(180°) orientation and FIG. 23B shows the u-joint 195 at approximately a150° orientation. The u-joint 195 may be used instead of the bevel gears52 a-c (see FIG. 4, for example) at the articulation point 14 of themain drive shaft assembly to articulate the end effector 12. FIGS. 24A-Bshow a torsion cable 197 that may be used in lieu of both the bevelgears 52 a-c and the u-joint 195 to realize articulation of the endeffector 12.

FIGS. 25-31 illustrate another embodiment of a motorized, two-strokesurgical cutting and fastening instrument 10 with power assist accordingto another embodiment of the present invention. The embodiment of FIGS.25-31 is similar to that of FIGS. 6-10 except that instead of thehelical gear drum 80, the embodiment of FIGS. 23-28 includes analternative gear drive assembly. The embodiment of FIGS. 25-31 includesa gear box assembly 200 including a number of gears disposed in a frame201, wherein the gears are connected between the planetary gear 72 andthe pinion gear 124 at the proximate end of the drive shaft 48. Asexplained further below, the gear box assembly 200 provides feedback tothe user via the firing trigger 20 regarding the deployment and loadingforce of the end effector 12. Also, the user may provide power to thesystem via the gear box assembly 200 to assist the deployment of the endeffector 12. In that sense, like the embodiments described above, theembodiment of FIGS. 23-32 is another power assist motorized instrument10 that provides feedback to the user regarding the loading forceexperienced by the instrument.

In the illustrated embodiment, the firing trigger 20 includes twopieces: a main body portion 202 and a stiffening portion 204. The mainbody portion 202 may be made of plastic, for example, and the stiffeningportion 204 may be made out of a more rigid material, such as metal. Inthe illustrated embodiment, the stiffening portion 204 is adjacent tothe main body portion 202, but according to other embodiments, thestiffening portion 204 could be disposed inside the main body portion202. A pivot pin 207 may be inserted through openings in the firingtrigger pieces 202, 204 and may be the point about which the firingtrigger 20 rotates. In addition, a spring 222 may bias the firingtrigger 20 to rotate in a counter clockwise direction. The spring 222may have a distal end connected to a pin 224 that is connected to thepieces 202, 204 of the firing trigger 20. The proximate end of thespring 222 may be connected to one of the handle exterior lower sidepieces 59, 60.

In the illustrated embodiment, both the main body portion 202 and thestiffening portion 204 includes gear portions 206, 208 (respectively) attheir upper end portions. The gear portions 206, 208 engage a gear inthe gear box assembly 200, as explained below, to drive the main driveshaft assembly and to provide feedback to the user regarding thedeployment of the end effector 12.

The gear box assembly 200 may include as shown, in the illustratedembodiment, six (6) gears. A first gear 210 of the gear box assembly 200engages the gear portions 206, 208 of the firing trigger 20. Inaddition, the first gear 210 engages a smaller second gear 212, thesmaller second gear 212 being coaxial with a large third gear 214. Thethird gear 214 engages a smaller fourth gear 216, the smaller fourthgear being coaxial with a fifth gear 218. The fifth gear 218 is a 90°bevel gear that engages a mating 90° bevel gear 220 (best shown in FIG.31) that is connected to the pinion gear 124 that drives the main driveshaft 48.

In operation, when the user retracts the firing trigger 20, a run motorsensor (not shown) is activated, which may provide a signal to the motor65 to rotate at a rate proportional to the extent or force with whichthe operator is retracting the firing trigger 20. This causes the motor65 to rotate at a speed proportional to the signal from the sensor. Thesensor is not shown for this embodiment, but it could be similar to therun motor sensor 110 described above. The sensor could be located in thehandle 6 such that it is depressed when the firing trigger 20 isretracted. Also, instead of a proportional-type sensor, an on/off typesensor may be used.

Rotation of the motor 65 causes the bevel gears 68, 70 to rotate, whichcauses the planetary gear 72 to rotate, which causes, via the driveshaft 76, the ring gear 122 to rotate. The ring gear 122 meshes with thepinion gear 124, which is connected to the main drive shaft 48. Thus,rotation of the pinion gear 124 drives the main drive shaft 48, whichcauses actuation of the cutting/stapling operation of the end effector12.

Forward rotation of the pinion gear 124 in turn causes the bevel gear220 to rotate, which causes, by way of the rest of the gears of the gearbox assembly 200, the first gear 210 to rotate. The first gear 210engages the gear portions 206, 208 of the firing trigger 20, therebycausing the firing trigger 20 to rotate counter clockwise when the motor65 provides forward drive for the end effector 12 (and to rotate counterclockwise when the motor 65 rotates in reverse to retract the endeffector 12). In that way, the user experiences feedback regardingloading force and deployment of the end effector 12 by way of the user'sgrip on the firing trigger 20. Thus, when the user retracts the firingtrigger 20, the operator will experience a resistance related to theload force experienced by the end effector 12. Similarly, when theoperator releases the firing trigger 20 after the cutting/staplingoperation so that it can return to its original position, the user willexperience a clockwise rotation force from the firing trigger 20 that isgenerally proportional to the reverse speed of the motor 65.

It should also be noted that in this embodiment the user can apply force(either in lieu of or in addition to the force from the motor 65) toactuate the main drive shaft assembly (and hence the cutting/staplingoperation of the end effector 12) through retracting the firing trigger20. That is, retracting the firing trigger 20 causes the gear portions206, 208 to rotate counter clockwise, which causes the gears of the gearbox assembly 200 to rotate, thereby causing the pinion gear 124 torotate, which causes the main drive shaft 48 to rotate.

Although not shown in FIGS. 25-31, the instrument 10 may further includereverse motor and stop motor sensors. As described above, the reversemotor and stop motor sensors may detect, respectively, the end of thecutting stroke (full deployment of the knife 32) and the end ofretraction operation (full retraction of the knife 32). A similarcircuit to that described above in connection with FIG. 11 may be usedto appropriately power the motor 65.

FIGS. 32-36 illustrate a two-stroke, motorized surgical cutting andfastening instrument 10 with power assist according to anotherembodiment. The embodiment of FIGS. 32-36 is similar to that of FIGS.25-31 except that in the embodiment of FIGS. 32-36, the firing trigger20 includes a lower portion 228 and an upper portion 230. Both portions228, 230 are connected to and pivot about a pivot pin 207 that isdisposed through each portion 228, 230. The upper portion 230 includes agear portion 232 that engages the first gear 210 of the gear boxassembly 200. The spring 222 is connected to the upper portion 230 suchthat the upper portion is biased to rotate in the clockwise direction.The upper portion 230 may also include a lower arm 234 that contacts anupper surface of the lower portion 228 of the firing trigger 20 suchthat when the upper portion 230 is caused to rotate clockwise the lowerportion 228 also rotates clockwise, and when the lower portion 228rotates counter clockwise the upper portion 230 also rotates counterclockwise. Similarly, the lower portion 228 includes a rotational stop238 that engages a shoulder of the upper portion 230. In that way, whenthe upper portion 230 is caused to rotate counter clockwise the lowerportion 228 also rotates counter clockwise, and when the lower portion228 rotates clockwise the upper portion 230 also rotates clockwise.

The illustrated embodiment also includes the run motor sensor 110 thatcommunicates a signal to the motor 65 that, in various embodiments, maycause the motor 65 to rotate at a speed proportional to the forceapplied by the operator when retracting the firing trigger 20. Thesensor 110 may be, for example, a rheostat or some other variableresistance sensor, as explained herein. In addition, the instrument 10may include reverse motor sensor 130 that is tripped or switched whencontacted by a front face 242 of the upper portion 230 of the firingtrigger 20. When activated, the reverse motor sensor 130 sends a signalto the motor 65 to reverse direction. Also, the instrument 10 mayinclude a stop motor sensor 142 that is tripped or actuated whencontacted by the lower portion 228 of the firing trigger 20. Whenactivated, the stop motor sensor 142 sends a signal to stop the reverserotation of the motor 65.

In operation, when an operator retracts the closure trigger 18 into thelocked position, the firing trigger 20 is retracted slightly (throughmechanisms known in the art, including U.S. Pat. No. 6,978,921 toFrederick Shelton, IV et. al and U.S. Pat. No. 6,905,057 to Jeffery S.Swayze et. al, which are incorporated herein by reference) so that theuser can grasp the firing trigger 20 to initiate the cutting/staplingoperation, as shown in FIGS. 32 and 33. At that point, as shown in FIG.33, the gear portion 232 of the upper portion 230 of the firing trigger20 moves into engagement with the first gear 210 of the gear boxassembly 200. When the operator retracts the firing trigger 20,according to various embodiments, the firing trigger 20 may rotate asmall amount, such as five degrees, before tripping the run motor sensor110, as shown in FIG. 34. Activation of the sensor 110 causes the motor65 to forward rotate at a rate proportional to the retraction forceapplied by the operator. The forward rotation of the motor 65 causes, asdescribed above, the main drive shaft 48 to rotate, which causes theknife 32 in the end effector 12 to be deployed (i.e., begin traversingthe channel 22). Rotation of the pinion gear 124, which is connected tothe main drive shaft 48, causes the gears 210-220 in the gear boxassembly 200 to rotate. Since the first gear 210 is in engagement withthe gear portion 232 of the upper portion 230 of the firing trigger 20,the upper portion 232 is caused to rotate counter clockwise, whichcauses the lower portion 228 to also rotate counter clockwise.

When the knife 32 is fully deployed (i.e., at the end of the cuttingstroke), the front face 242 of the upper portion 230 trips the reversemotor sensor 130, which sends a signal to the motor 65 to reverserotational directional. This causes the main drive shaft assembly toreverse rotational direction to retract the knife 32. Reverse rotationof the main drive shaft assembly also causes the gears 210-220 in thegear box assembly to reverse direction, which causes the upper portion230 of the firing trigger 20 to rotate clockwise, which causes the lowerportion 228 of the firing trigger 20 to rotate clockwise until the lowerportion 228 trips or actuates the stop motor sensor 142 when the knife32 is fully retracted, which causes the motor 65 to stop. In that way,the user experiences feedback regarding deployment of the end effector12 by way of the user's grip on the firing trigger 20. Thus, when theuser retracts the firing trigger 20, the operator will experience aresistance related to the deployment of the end effector 12 and, inparticular, to the loading force experienced by the knife 32. Similarly,when the operator releases the firing trigger 20 after thecutting/stapling operation so that it can return to its originalposition, the user will experience a clockwise rotation force from thefiring trigger 20 that is generally proportional to the reverse speed ofthe motor 65.

It should also be noted that in this embodiment the user can apply force(either in lieu of or in addition to the force from the motor 65) toactuate the main drive shaft assembly (and hence the cutting/staplingoperation of the end effector 12) through retracting the firing trigger20. That is, retracting the firing trigger 20 causes the gear portion232 of the upper portion 230 to rotate counter clockwise, which causesthe gears of the gear box assembly 200 to rotate, thereby causing thepinion gear 124 to rotate, which causes the main drive shaft assembly torotate.

The above-described embodiments employed power-assist user feedbacksystems, with or without adaptive control (e.g., using a sensor 110,130, and 142 outside of the closed loop system of the motor 65, geardrive train, and end effector 12) for a two-stroke, motorized surgicalcutting and fastening instrument. That is, force applied by the user inretracting the firing trigger 20 may be added to the force applied bythe motor 65 by virtue of the firing trigger 20 being geared into(either directly or indirectly) the gear drive train between the motor65 and the main drive shaft 48. In other embodiments of the presentinvention, the user may be provided with tactile feedback regarding theposition of the knife 32 in the end effector, but without having thefiring trigger 20 geared into the gear drive train. FIGS. 37-40illustrate a motorized surgical cutting and fastening instrument withsuch a tactile position feedback system.

In the illustrated embodiment of FIGS. 37-40, the firing trigger 20 mayhave a lower portion 228 and an upper portion 230, similar to theinstrument 10 shown in FIGS. 32-36. Unlike the embodiment of FIG. 32-36,however, the upper portion 230 does not have a gear portion that mateswith part of the gear drive train. Instead, the instrument includes asecond motor 265 with a threaded rod 266 threaded therein. The threadedrod 266 reciprocates longitudinally in and out of the motor 265 as themotor 265 rotates, depending on the direction of rotation. Theinstrument 10 also includes an encoder 268 that is responsive to therotations of the main drive shaft 48 for translating the incrementalangular motion of the main drive shaft 48 (or other component of themain drive assembly) into a corresponding series of digital signals, forexample. In the illustrated embodiment, the pinion gear 124 includes aproximate drive shaft 270 that connects to the encoder 268.

The instrument 10 also includes a control circuit (not shown), which maybe implemented using a microcontroller or some other type of integratedcircuit, that receives the digital signals from the encoder 268. Basedon the signals from the encoder 268, the control circuit may calculatethe stage of deployment of the knife 32 in the end effector 12. That is,the control circuit can calculate if the knife 32 is fully deployed,fully retracted, or at an intermittent stage. Based on the calculationof the stage of deployment of the end effector 12, the control circuitmay send a signal to the second motor 265 to control its rotation tothereby control the reciprocating movement of the threaded rod 266.

In operation, as shown in FIG. 37, when the closure trigger 18 is notlocked into the clamped position, the firing trigger 20 rotated awayfrom the pistol grip portion 26 of the handle 6 such that the front face242 of the upper portion 230 of the firing trigger 20 is not in contactwith the proximate end of the threaded rod 266. When the operatorretracts the closure trigger 18 and locks it in the clamped position,the firing trigger 20 rotates slightly towards the closure trigger 20 sothat the operator can grasp the firing trigger 20, as shown in FIG. 38.In this position, the front face 242 of the upper portion 230 contactsthe proximate end of the threaded rod 266.

As the user then retracts the firing trigger 20, after an initialrotational amount (e.g. 5 degrees of rotation) the run motor sensor 110may be activated such that, as explained above, the sensor 110 sends asignal to the motor 65 to cause it to rotate at a forward speedproportional to the amount of retraction force applied by the operatorto the firing trigger 20. Forward rotation of the motor 65 causes themain drive shaft 48 to rotate via the gear drive train, which causes theknife 32 and sled 33 to travel down the channel 22 and sever tissueclamped in the end effector 12. The control circuit receives the outputsignals from the encoder 268 regarding the incremental rotations of themain drive shaft assembly and sends a signal to the second motor 265 tocause the second motor 265 to rotate, which causes the threaded rod 266to retract into the motor 265. This allows the upper portion 230 of thefiring trigger 20 to rotate counter clockwise, which allows the lowerportion 228 of the firing trigger to also rotate counter clockwise. Inthat way, because the reciprocating movement of the threaded rod 266 isrelated to the rotations of the main drive shaft assembly, the operatorof the instrument 10, by way of his/her grip on the firing trigger 20,experiences tactile feedback as to the position of the end effector 12.The retraction force applied by the operator, however, does not directlyaffect the drive of the main drive shaft assembly because the firingtrigger 20 is not geared into the gear drive train in this embodiment.

By virtue of tracking the incremental rotations of the main drive shaftassembly via the output signals from the encoder 268, the controlcircuit can calculate when the knife 32 is fully deployed (i.e., fullyextended). At this point, the control circuit may send a signal to themotor 65 to reverse direction to cause retraction of the knife 32. Thereverse direction of the motor 65 causes the rotation of the main driveshaft assembly to reverse direction, which is also detected by theencoder 268. Based on the reverse rotation detected by the encoder 268,the control circuit sends a signal to the second motor 265 to cause itto reverse rotational direction such that the threaded rod 266 starts toextend longitudinally from the motor 265. This motion forces the upperportion 230 of the firing trigger 20 to rotate clockwise, which causesthe lower portion 228 to rotate clockwise. In that way, the operator mayexperience a clockwise force from the firing trigger 20, which providesfeedback to the operator as to the retraction position of the knife 32in the end effector 12. The control circuit can determine when the knife32 is fully retracted. At this point, the control circuit may send asignal to the motor 65 to stop rotation.

According to other embodiments, rather than having the control circuitdetermine the position of the knife 32, reverse motor and stop motorsensors may be used, as described above. In addition, rather than usinga proportional sensor 110 to control the rotation of the motor 65, anon/off switch or sensor can be used. In such an embodiment, the operatorwould not be able to control the rate of rotation of the motor 65.Rather, it would rotate at a preprogrammed rate.

FIGS. 41-43 illustrate an exemplary embodiment of a mechanicallyactuated endocutter, and in particular the handle 6, shaft 8 and endeffector 12 thereof. Further details of a mechanically actuatedendocutter may be found in U.S. patent application Ser. No. 11/052,632entitled, MULTI-STROKE MECHANISM WITH AUTOMATIC END OF STROKERETRACTION, now U.S. Pat. No. 7,083,075 which is incorporated herein byreference. With reference to FIG. 41, the end effector 12 responds tothe closure motion from the handle 6 (not depicted in FIG. 41) first byincluding an anvil face 1002 connecting to an anvil proximal end 1004that includes laterally projecting anvil pivot pins 25 that are proximalto a vertically projecting anvil tab 27. The anvil pivot pins 25translate within kidney shaped openings 1006 in the staple channel 22 toopen and close anvil 24 relative to channel 22. The tab 27 engages abent tab 1007 extending inwardly in tab opening 45 on a distal end 1008of the closure tube 1005, the latter distally terminating in a distaledge 1008 that pushes against the anvil face 1002. Thus, when theclosure tube 1005 moves proximally from its open position, the bent tab1007 of the closure tube 1005 draws the anvil tab 27 proximally, and theanvil pivot pins 25 follow the kidney shaped openings 1006 of the staplechannel 22 causing the anvil 24 to simultaneously translate proximallyand rotate upward to the open position. When the closure tube 1005 movesdistally, the bent tab 1007 in the tab opening 45 releases from theanvil tab 27 and the distal edge 1008 pushes on the anvil face 1002,closing the anvil 24.

With continued reference to FIG. 41, the shaft 8 and end effector 12also include components that respond to a firing motion of a firing rod1010. In particular, the firing rod 1010 rotatably engages a firingtrough member 1012 having a longitudinal recess 1014. Firing troughmember 1012 moves longitudinally within frame 1016 in direct response tolongitudinal motion of firing rod 1010. A longitudinal slot 1018 in theclosure tube 1005 operably couples with the right and left exterior sidehandle pieces 61, 62 of the handle 6 (not shown in FIG. 41). The lengthof the longitudinal slot 1018 in the closure tube 1005 is sufficientlylong to allow relative longitudinal motion with the handle pieces 61, 62to accomplish firing and closure motions respectively with the couplingof the handle pieces 61, 62 passing on through a longitudinal slot 1020in the frame 1016 to slidingly engage the longitudinal recess 1014 inthe frame trough member 1012.

The distal end of the frame trough member 1012 is attached to a proximalend of a firing bar 1022 that moves within the frame 1016, specificallywithin a guide 1024 therein, to distally project the knife 32 into theend effector 12. The end effector 12 includes a staple cartridge 34 thatis actuated by the knife 32. The staple cartridge 34 has a tray 290 thatholds a staple cartridge body 1030, a wedge sled driver 33, stapledrivers 1034 and staples 1036. It will be appreciated that the wedgesled driver 33 longitudinally moves within a firing recess (not shown)located between the cartridge tray 290 and the cartridge body 1030. Thewedge sled driver 33 presents camming surfaces that contact and lift thestaple drivers 1034 upward, driving the staples 1036. The staplecartridge body 1030 further includes a proximally open, vertical slot1031 for passage of the knife 32. Specifically, a cutting surface 1027is provided along a distal end of knife 32 to cut tissue after it isstapled.

It should be appreciated that the shaft 8 is shown in FIG. 4 as anon-articulating shaft. Nonetheless, applications of the presentinvention may include instruments capable of articulation, for example,as such shown above with reference to FIGS. 1-4 and described in thefollowing U.S. patents and patent applications, the disclosure of eachbeing hereby incorporated by reference in their entirety: (1) SURGICALINSTRUMENT INCORPORATING AN ARTICULATION MECHANISM HAVING ROTATION ABOUTTHE LONGITUDINAL AXIS, by Frederick E. Shelton IV, Brian J. Hemmelgarn,Jeffrey S. Swayze, Kenneth S. Wales, filed Jul. 9, 2003, now U.S. Pat.No. 7,111,769; (2) SURGICAL STAPLING INSTRUMENT INCORPORATING ANARTICULATION JOINT FOR A FIRING TRACK, U.S. Pat. No. 6,786,382, to BrianJ. Hemmelgarn; (3) A SURGICAL INSTRUMENT WITH A LATERAL-MOVINGARTICULATION CONTROL, U.S. Pat. No.6,981,628, to Jeffrey S. Swayze; (4)SURGICAL STAPLING INSTRUMENT INCORPORATING A TAPERED FIRING BAR FORINCREASED FLEXIBILITY AROUND THE ARTICULATION JOINT, U.S. Pat. No.6,964,363, to Frederick E. Shelton IV, Michael Setser, Bruce WeisenburghII; and (5) SURGICAL STAPLING INSTRUMENT HAVING ARTICULATION JOINTSUPPORT PLATES FOR SUPPORTING A FIRING BAR, U.S. Patent ApplicationPublication No. 2005/0006431, by Jeffrey S. Swayze, Joseph CharlesHueil, filed Jul. 9, 2003, now U.S. Pat. No. 7,055,731.

FIGS. 42-43 show an embodiment of the handle 6 that is configured foruse in a mechanically actuated endocutter along with the embodiment ofthe shaft 8 and end effector 12 as shown above in FIG. 41. It will beappreciated that any suitable handle design may be used to mechanicallyclose and fire the end effector 12. In FIGS. 42-43, the handle 6 of thesurgical stapling and severing instrument 10 includes a linkedtransmission firing mechanism 1060 that provides features such asincreased strength, reduced handle size, minimized binding, etc.

Closure of the end effector 12 (not shown in FIGS. 42-43) is caused bydepressing the closure trigger 18 toward the pistol grip 26 of handle 6.The closure trigger 18 pivots about a closure pivot pin 252 that iscoupled to right and left exterior lower side pieces 59, 60 the handle6, causing an upper portion 1094 of the closure trigger 18 to moveforward. The closure tube 1005 receives this closure movement via theclosure yoke 250 that is pinned to a closure link 1042 and to the upperportion 1094 of the closure trigger 18 respectively by a closure yokepin 1044 and a closure link pin 1046.

In the fully open position of FIG. 42, the upper portion 1094 of theclosure trigger 18 contacts and holds a locking arm 1048 of the pivotingclosure release button 30 in the position shown. When the closuretrigger 18 reaches its fully depressed position, the closure trigger 18releases the locking arm 1048 and an abutting surface 1050 rotates intoengagement with a distal rightward notch 1052 of the pivoting lockingarm 1048, holding the closure trigger 18 in this clamped or closedposition. A proximal end of the locking arm 1048 pivots about a lateralpivotal connection 1054 with the pieces 59, 60 to expose the closurerelease button 30. An intermediate, distal side 1056 of the closurerelease button 30 is urged proximally by a compression spring 1058,which is compressed between a housing structure 1040 and closure releasebutton 30. The result is that the closure release button 30 urges thelocking arm 1048 counterclockwise (when viewed from the left) intolocking contact with the abutting surface 1050 of closure trigger 18,which prevents unclamping of closure trigger 18 when the linkedtransmission firing system 1040 is in an un-retracted condition.

With the closure trigger 18 retracted and fully depressed, the firingtrigger 20 is unlocked and may be depressed toward the pistol grip 26,multiple times in this embodiment, to effect firing of the end effector12. As depicted, the linked transmission firing mechanism 1060 isinitially retracted, urged to remain in this position by a combinationtension/compression spring 1062 that is constrained within the pistolgrip 26 of the handle 6, with its nonmoving end 1063 connected to thepieces 59, 60 and a moving end 1064 connected to a downwardly flexed andproximal, retracted end 1067 of a steel band 1066.

A distally-disposed end 1068 of the steel band 1066 is attached to alink coupling 1070 for structural loading, which in turn is attached toa front link 1072 a of a plurality of links 1072 a-1072 d that form alinked rack 1074. Linked rack 1074 is flexible yet has distal links thatform a straight rigid rack assembly that may transfer a significantfiring force through the firing rod 1010 in the shaft 6, yet readilyretract into the pistol grip 26 to minimize the longitudinal length ofthe handle 6. It should be appreciated that the combinationtension/compression spring 1062 increases the amount of firing travelavailable while essentially reducing the minimum length by half over asingle spring.

The firing trigger 20 pivots about a firing trigger pin 96 that isconnected to the handle pieces 59, 60. An upper portion 228 of thefiring trigger 20 moves distally about the firing trigger pin 96 as thefiring trigger 20 is depressed towards pistol grip 26, stretching aproximally placed firing trigger tension spring 222 proximally connectedbetween the upper portion 228 of the firing trigger 20 and the pieces59, 60. The upper portion 228 of the firing trigger 20 engages thelinked rack 1074 during each firing trigger depression by a tractionbiasing mechanism 1078 that also disengages when the firing trigger 20is released. Firing trigger tension spring 222 urges the firing trigger20 distally when released and disengages the traction biasing mechanism1078.

As the linked transmission firing mechanism 1040 actuates, an idler gear1080 is rotated clockwise (as viewed from the left side) by engagementwith a toothed upper surface 1082 of the linked rack 1074. This rotationis coupled to an indicator gear 1084, which thus rotatescounterclockwise in response to the idler gear 1080. Both the idler gear1080 and indicator gear 1084 are rotatably connected to the pieces 59,60 of the handle 6. The gear relationship between the linked rack 1074,idler gear 1080 and indicator gear 1084 may be advantageously selectedso that the toothed upper surface 1082 has tooth dimensions that aresuitably strong and that the indicator gear 1084 makes no more than onerevolution during the full firing travel of the linked transmissionfiring mechanism 1060.

As described in greater detail below, the indicator gear 1084 performsat least four functions. First, when the linked rack 1074 is fullyretracted and both triggers 18, 20 are open as shown in FIG. 42, anopening 1086 in a circular ridge 1088 on the left side of the indicatorgear 1084 is presented to an upper surface 1090 of the locking arm 1048.Locking arm 1048 is biased into the opening 1086 by contact with theclosure trigger 18, which in turn is urged to the open position by aclosure tension spring 1092. Closure trigger tension spring 1092 isconnected proximally to the upper portion 1094 of the closure trigger 18and the handle pieces 59, 60, and thus has energy stored during closingof the closure trigger 18 that urges the closure trigger 18 distally toits unclosed position.

A second function of the indicator gear 1084 is that it is connected tothe indicating retraction knob 1096 externally disposed on the handle 6.Thus, the indicator gear 1084 communicates the relative position of thefiring mechanism 1060 to the indicating retraction knob 1096 so that thesurgeon has a visual indication of how many strokes of the firingtrigger 20 are required to complete firing.

A third function of the indicator gear 1084 is to longitudinally andangularly move an anti-backup release lever 1098 of an anti-backupmechanism (one-way clutch mechanism) 1097 as the surgical stapling andsevering instrument 10 is operated. During the firing strokes, proximalmovement of anti-backup release lever 1098 by indicator gear 1084activates the anti-backup mechanism 1097 that allows distal movement offiring bar 1010 and prevents proximal motion of firing bar 1010. Thismovement also extends the anti-backup release button 1100 from theproximal end of the handle pieces 59, 60 for the operator to actuateshould the need arise for the linked transmission firing mechanism 1060to be retracted during the firing strokes. After completion of thefiring strokes, the indicator gear 1084 reverses direction of rotationas the firing mechanism 1060 retracts. The reversed rotation deactivatesthe anti-backup mechanism 1097, withdraws the anti-backup release button1100 into the handle 6, and rotates the anti-backup release lever 1098laterally to the right to allow continued reverse rotation of theindicator gear 1084.

A fourth function of the indicator gear 1084 is to receive a manualrotation from the indicating retraction knob 1096 (clockwise in thedepiction of FIG. 42) to retract the firing mechanism 1060 withanti-backup mechanism 1097 unlocked, thereby overcoming any binding inthe firing mechanism 1060 that is not readily overcome by thecombination tension/compression spring 1062. This manual retractionassistance may be employed after a partial firing of the firingmechanism 1060 that would otherwise be prevented by the anti-backupmechanism 1097 that withdraws the anti-backup release button 1100 sothat the latter may not laterally move the anti-backup release lever1098.

Continuing with FIGS. 42-43, anti-backup mechanism 1097 consists of theoperator accessible anti-backup release lever 1098 operably coupled atthe proximal end to the anti-backup release button 1100 and at thedistal end to an anti-backup yoke 1102. In particular, a distal end 1099of the anti-backup release lever 1098 is engaged to the anti-backup yoke1102 by an anti-backup yoke pin 1104. The anti-backup yoke 1102 moveslongitudinally to impart a rotation to an anti-backup cam slot tube 1106that is longitudinally constrained by the handle pieces 59, 90 and thatencompasses the firing rod 1010 distally to the connection of the firingrod 1010 to the link coupling 1070 of the linked rack 1074. Theanti-backup yoke 1102 communicates the longitudinal movement from theanti-backup release lever 1098 via a cam slot tube pin 1108 to theanti-backup cam slot tube 1106. That is, longitudinal movement of camslot tube pin 1108 in an angled slot in the anti-backup cam slot tube1106 rotates the anti-backup cam slot tube 1106.

Trapped between a proximal end of the frame 1016 and the anti-backup camslot tube 1106 respectively are an anti-backup compression spring 1110,an anti-backup plate 1112, and an anti-backup cam tube 1114. Asdepicted, proximal movement of the firing rod 1010 causes theanti-backup plate 1112 to pivot top to the rear, presenting an increasedfrictional contact to the firing rod 1010 that resists further proximalmovement of the firing rod 1010.

This anti-backup plate 1112 pivots in a manner similar to that of ascreen door lock that holds open a screen door when the anti-backup camslot tube 1106 is closely spaced to the anti-backup cam tube 1114.Specifically, the anti-backup compression spring 1110 is able to actupon a top surface of the plate 1112 to tip the anti-backup plate 1112to its locked position. Rotation of the anti-backup cam slot tube 1106causes a distal camming movement of the anti-backup cam tube 1114thereby forcing the top of the anti-backup plate 1112 distally,overcoming the force from the anti-backup compression spring 1110, thuspositioning the anti-backup plate 1112 in an untipped (perpendicular),unlocked position that allows proximal retraction of the firing rod1010.

With particular reference to FIG. 43, the traction biasing mechanism1078 is depicted as being composed of a pawl 1116 that has a distallyprojecting narrow tip 1118 and a rightwardly projecting lateral pin 1120at its proximal end that is rotatably inserted through a hole 1076 inthe upper portion 230 of the firing trigger 20. On the right side of thefiring trigger 20 the lateral pin 1120 receives a biasing member,depicted as biasing wheel 1122. As the firing trigger 20 translates foreand aft, the biasing wheel 1122 traverses an arc proximate to the righthalf piece 59 of the handle 6, overrunning at its distal portion oftravel a biasing ramp 1124 integrally formed in the right half piece 59.The biasing wheel 1122 may advantageously be formed from a resilient,frictional material that induces a counterclockwise rotation (whenviewed from the left) into the lateral pin 1120 of the pawl 1116, thustraction biasing the distally projecting narrow tip 1118 downward into aramped central track 1075 of the nearest link 1072 a-d to engage thelinked rack 1074.

As the firing trigger 20 is released, the biasing wheel 1122 thustractionally biases the pawl 1116 in the opposite direction, raising thenarrow tip 1118 from the ramped central track 1075 of the linked rack1074. To ensure disengagement of the tip 1118 under high load conditionsand at nearly full distal travel of the pawl 1116, the right side of thepawl 1116 ramps up onto a proximally and upwardly facing beveled surface1126 on the right side of the closure yoke 250 to disengage the narrowtip 1118 from the ramped central track 1075. If the firing trigger 20 isreleased at any point other than full travel, the biasing wheel 1122 isused to lift the narrow tip 1118 from the ramped central track 1075.Whereas a biasing wheel 1122 is depicted, it should be appreciated thatthe shape of the biasing member or wheel 1122 is illustrative and may bevaried to accommodate a variety of shapes that use friction or tractionto engage or disengage the firing of the end effector 12.

Various embodiments of the surgical instrument 10 have the capability torecord instrument conditions at one or more times during use. FIG. 44shows a block diagram of a system 2000 for recording conditions of theinstrument 10. It will be appreciated that the system 2000 may beimplemented in embodiments of the instrument 10 having motorized ormotor-assisted firing, for example, as described above with reference toFIGS. 1-40, as well as embodiments of the instrument 10 havingmechanically actuated firing, for example, as described above withreference to FIGS. 41-43.

The system 2000 may include various sensors 2002, 2004, 2006, 2008, 136a, 136 b for sensing instrument conditions. The sensors may bepositioned, for example, on or within the instrument 10. In variousembodiments, the sensors may be dedicated sensors that provide outputonly for the system 2000, or may be dual-use sensors that perform otherfunctions with in the instrument 10. For example, sensors 110, 130, 142described above may be configured to also provide output to the system2000.

Directly or indirectly, each sensor provides a signal to the memorydevice 2001, which records the signals as described in more detailbelow. The memory device 2001 may be any kind of device capable ofstoring or recording sensor signals. For example, the memory device 2001may include a microprocessor, an Electrically Erasable Programmable ReadOnly Memory (EEPROM), or any other suitable storage device. The memorydevice 2001 may record the signals provided by the sensors in anysuitable way. For example, in one embodiment, the memory device 2001 mayrecord the signal from a particular sensor when that signal changesstates. In another embodiment, the memory device 2001 may record a stateof the system 2000, e.g., the signals from all of the sensors includedin the system 2000, when the signal from any sensor changes states. Thismay provide a snap-shot of the state of the instrument 10. In variousembodiments, the memory device 2001 and/or sensors may be implemented toinclude 1-WIRE bus products available from DALLAS SEMICONDUCTOR such as,for example, a 1-WIRE EEPROM.

In various embodiments, the memory device 2001 is externally accessible,allowing an outside device, such as a computer, to access the instrumentconditions recorded by the memory device 2001. For example, the memorydevice 2001 may include a data port 2020. The data port 2020 may providethe stored instrument conditions according to any wired or wirelesscommunication protocol in, for example, serial or parallel format. Thememory device 2001 may also include a removable medium 2021 in additionto or instead of the output port 2020. The removable medium 2021 may beany kind of suitable data storage device that can be removed from theinstrument 10. For example, the removable medium 2021 may include anysuitable kind of flash memory, such as a Personal Computer Memory CardInternational Association (PCMCIA) card, a COMPACTFLASH card, aMULTIMEDIA card, a FLASHMEDIA card, etc. The removable medium 2021 mayalso include any suitable kind of disk-based storage including, forexample, a portable hard drive, a compact disk (CD), a digital videodisk (DVD), etc.

The closure trigger sensor 2002 senses a condition of the closuretrigger 18. FIGS. 45 and 46 show an exemplary embodiment of the closuretrigger sensor 2002. In FIGS. 45 and 46, the closure trigger sensor 2002is positioned between the closure trigger 18 and closure pivot pin 252.It will be appreciated that pulling the closure trigger 18 toward thepistol grip 26 causes the closure trigger 18 to exert a force on theclosure pivot pin 252. The sensor 2002 may be sensitive to this force,and generate a signal in response thereto, for example, as describedabove with respect to sensor 110 and FIGS. 10A and 10B. In variousembodiments, the closure trigger sensor 2002 may be a digital sensorthat indicates only whether the closure trigger 18 is actuated or notactuated. In other various embodiments, the closure trigger sensor 2002may be an analog sensor that indicates the force exerted on the closuretrigger 18 and/or the position of the closure trigger 18. If the closuretrigger sensor 2002 is an analog sensor, an analog-to-digital convertermay be logically positioned between the sensor 2002 and the memorydevice 2001. Also, it will be appreciated that the closure triggersensor 2002 may take any suitable form and be placed at any suitablelocation that allows sensing of the condition of the closure trigger.

The anvil closure sensor 2004 may sense whether the anvil 24 is closed.FIG. 47 shows an exemplary anvil closure sensor 2004. The sensor 2004 ispositioned next to, or within the kidney shaped openings 1006 of thestaple channel 22 as shown. As the anvil 24 is closed, anvil pivot pins25 slides through the kidney shaped openings 1006 and into contact withthe sensor 2004, causing the sensor 2004 to generate a signal indicatingthat the anvil 24 is closed. The sensor 2004 may be any suitable kind ofdigital or analog sensor including a proximity sensor, etc. It will beappreciated that when the anvil closure sensor 2004 is an analog sensor,an analog-to-digital converter may be included logically between thesensor 2004 and the memory device 2001.

Anvil closure load sensor 2006 is shown placed on an inside bottomsurface of the staple channel 22. In use, the sensor 2006 may be incontact with a bottom side of the staple cartridge 34 (not shown in FIG.46). As the anvil 24 is closed, it exerts a force on the staplecartridge 34 which is transferred to the sensor 2006. In response, thesensor 2006 generates a signal. The signal may be an analog signalproportional to the force exerted on the sensor 2006 by the staplecartridge 34 and due to the closing of the anvil 24. Referring the FIG.44, the analog signal may be provided to an analog-to-digital converter2014, which converts the analog signal to a digital signal beforeproviding it to the memory device 2001. It will be appreciated thatembodiments where the sensor 2006 is a digital or binary sensor may notinclude analog-to-digital converter 2014.

The firing trigger sensor 110 senses the position and/or state of thefiring trigger 20. In motorized or motor-assisted embodiments of theinstrument, the firing trigger sensor may double as the run motor sensor110 described above. In addition, the firing trigger sensor 110 may takeany of the forms described above, and may be analog or digital. FIGS. 45and 46 show an additional embodiment of the firing trigger sensor 110.In FIGS. 45 and 46, the firing trigger sensor is mounted between firingtrigger 20 and firing trigger pivot pin 96. When firing trigger 20 ispulled, it will exert a force on firing trigger pivot pin 96 that issensed by the sensor 110. Referring to FIG. 44, In embodiments where theoutput of the firing trigger sensor 110 is analog, analog-to-digitalconverter 2016 is included logically between the firing trigger sensor110 and the memory device 2001.

The knife position sensor 2008 senses the position of the knife 32 orcutting surface 1027 within the staple channel 22. FIGS. 47 and 48 showembodiments of a knife position sensor 2008 that are suitable for usewith the mechanically actuated shaft 8 and end effector 12 shown in FIG.41. The sensor 2008 includes a magnet 2009 coupled to the firing bar1022 of the instrument 10. A coil 288 a is positioned around the firingbar 1022, and may be installed; for example, along the longitudinalrecess 1014 of the firing trough member 1012 (see FIG. 41). As the knife32 and cutting surface 1027 are reciprocated through the staple channel22, the firing bar 1022 and magnet 2009 may move back and forth throughthe coil 288 a. This motion relative to the coil induces a voltage inthe coil proportional to the position of the firing rod within the coiland the cutting edge 1027 within the staple channel 22. This voltage maybe provided to the memory device 2001, for example, viaanalog-to-digital converter 2018.

In various embodiments, the knife position sensor 2008 may instead beimplemented as a series of digital sensors (not shown) placed at variouspositions on or within the shaft 8. The digital sensors may sense afeature of the firing bar 1022 such as, for example, magnet 2009, as thefeature reciprocates through the shaft 8. The position of the firing bar1022 within the shaft 8, and by extension, the position of the knife 32within the staple channel 22, may be approximated as the position of thelast digital sensor tripped.

It will be appreciated that the knife position may also be sensed inembodiments of the instrument 10 having a rotary driven end effector 12and shaft 8, for example, as described above, with reference to FIGS.3-6. An encoder, such as encoder 268, may be configured to generate asignal proportional to the rotation of the helical screw shaft 36, orany other drive shaft or gear. Because the rotation of the shaft 36 andother drive shafts and gears is proportional to the movement of theknife 32 through the channel 22, the signal generated by the encoder 268is also proportional to the movement of the knife 32. Thus, the outputof the encoder 268 may be provided to the memory device 2001.

The cartridge present sensor 136 a may sense the presence of the staplecartridge 34 within the staple channel 22. In motorized ormotor-assisted instruments, the cartridge present sensor 136 a maydouble as the cartridge lock-out sensor 136 described above withreference to FIG. 11. FIGS. 50A and 50B show an embodiment of thecartridge present sensor 136 a. In the embodiment shown, the cartridgepresent sensor 136 a includes two contacts, 288 a and 288 b. When nocartridge 34 is present, the contacts 288 a, 288 b form an open circuit.When a cartridge 34 is present, the cartridge tray 290 of the staplecartridge 34 contacts the contacts 288 a, 288 b, a closed circuit isformed. When the circuit is open, the sensor 136 a may output a logiczero. When the circuit is closed, the sensor 136 a may output a logicone. The output of the sensor 136 a is provided to memory device 2001,as shown in FIG. 44.

The cartridge condition sensor 136 b may indicate whether a cartridge 34installed within the staple channel 22 has been fired or spent. As theknife 32 is translated through the end effector 12, it pushes the sled33, which fires the staple cartridge. Then the knife 32 is translatedback to its original position, leaving the sled 33 at the distal end ofthe cartridge. Without the sled 33 to guide it, the knife 32 may fallinto lock-out pocket 2022. Sensor 136 b may sense whether the knife 32is present in the lock-out pocket 2022, which indirectly indicateswhether the cartridge 34 has been spent. It will be appreciated that invarious embodiments, sensor 136 b may directly sense the present of thesled at the proximate end of the cartridge 34, thus eliminating the needfor the knife 32 to fall into the lock-out pocket 2022.

FIGS. 52A and 52B depict a process flow 2200 for operating embodimentsof the surgical instrument 10 configured as an endocutter and having thecapability to record instrument conditions according to variousembodiments. At box 2202, the anvil 24 of the instrument 10 may beclosed. This causes the closure trigger sensor 2002 and or the anvilclosure sensor 2006 to change state. In response, the memory device 2001may record the state of all of the sensors in the system 2000 at box2203. At box 2204, the instrument 10 may be inserted into a patient.When the instrument is inserted, the anvil 24 may be opened and closedat box 2206, for example, to manipulate tissue at the surgical site.Each opening and closing of the anvil 24 causes the closure triggersensor 2002 and/or the anvil closure sensor 2004 to change state. Inresponse, the memory device 2001 records the state of the system 2000 atbox 2205.

At box 2208, tissue is clamped for cutting and stapling. If the anvil 24is not closed at decision block 2210, continued clamping is required. Ifthe anvil 24 is closed, then the sensors 2002, 2004 and/or 2006 maychange state, prompting the memory device 2001 to record the state ofthe system at box 2213. This recording may include a closure pressurereceived from sensor 2006. At box 2212, cutting and stapling may occur.Firing trigger sensor 110 may change state as the firing trigger 20 ispulled toward the pistol grip 26. Also, as the knife 32 moves throughthe staple channel 22, knife position sensor 2008 will change state. Inresponse, the memory device 2001 may record the state of the system 2000at box 288 b.

When the cutting and stapling operations are complete, the knife 32 mayreturn to a pre-firing position. Because the cartridge 34 has now beenfired, the knife 32 may fall into lock-out pocket 2022, changing thestate of cartridge condition sensor 136 b and triggering the memorydevice 2001 to record the state of the system 2000 at box 2015. Theanvil 24 may then be opened to clear the tissue. This may cause one ormore of the closure trigger sensor 2002, anvil closure sensor 2004 andanvil closure load sensor 2006 to change state, resulting in arecordation of the state of the system 2000 at box 2017. After thetissue is cleared, the anvil 24 may be again closed at box 2220. Thiscauses another state change for at least sensors 2002 and 2004, which inturn causes the memory device 2001 to record the state of the system atbox 2019. Then the instrument 10 may be removed from the patient at box2222.

If the instrument 10 is to be used again during the same procedure, theanvil may be opened at box 2224, triggering another recordation of thesystem state at box 2223. The spent cartridge 34 may be removed from theend effector 12 at box 2226. This causes cartridge present sensor 136 ato change state and cause a recordation of the system state at box 2225.Another cartridge 34 may be inserted at box 2228. This causes a statechange in the cartridge present sensor 136 a and a recordation of thesystem state at box 2227. If the other cartridge 34 is a new cartridge,indicated at decision block 2230, its insertion may also cause a statechange to cartridge condition sensor 136 b. In that case, the systemstate may be recorded at box 2231.

FIG. 53 shows an exemplary memory map 2300 from the memory device 2001according to various embodiments. The memory map 2300 includes a seriesof columns 2302, 2304, 2306, 2308, 2310, 2312, 2314, 2316 and rows (notlabeled). Column 2302 shows an event number for each of the rows. Theother columns represent the output of one sensor of the system 2000. Allof the sensor readings recorded at a given time may be recorded in thesame row under the same event number. Hence, each row represents aninstance where one or more of the signals from the sensors of the system2000 are recorded.

Column 2304 lists the closure load recorded at each event. This mayreflect the output of anvil closure load sensor 2006. Column 2306 liststhe firing stroke position. This may be derived from the knife positionsensor 2008. For example, the total travel of the knife 32 may bedivided into partitions. The number listed in column 2306 may representthe partition where the knife 32 is currently present. The firing loadis listed in column 2308. This may be derived from the firing triggersensor 110. The knife position is listed at column 2310. The knifeposition may be derived from the knife position sensor 2008 similar tothe firing stroke. Whether the anvil 24 is open or closed may be listedat column 2312. This value may be derived from the output of the anvilclosure sensor 2004 and/or the anvil closure load sensor 2006. Whetherthe sled 33 is present, or whether the cartridge 34 is spent, may beindicated at column 2314. This value may be derived from the cartridgecondition sensor 136 b. Finally, whether the cartridge 34 is present maybe indicated a column 2316. This value may be derived from cartridgepresent sensor 136 a. It will be appreciated that various other valuesmay be stored at memory device 2001 including, for example, the end andbeginning of firing strokes, for example, as measured by sensors 130,142.

As indicated above, there are several steps within the function of astapler that generally must be accomplished in an established order. Forexample, once the closure trigger is clamped, the firing cycle may beactuated. After the knife has been fully deployed, then retraction ofthe system is the next sequential step. With the inclusion of a powersource other than the user (i.e. batteries or pneumatics) the ability toreduce user initiated steps (and therefore device complexity) the systemitself, as was discussed above, can begin to accomplish these stepsitself.

It may be desirable, however, for the user to intuitively be able todelay, slow or stop these otherwise “automatic” actuations. For example,the same actuation button that would allow for firing initiation in atactile feedback device like the devices disclosed in U.S. patentapplication Ser. No. 11/344,035, now U.S. Pat. No. 7,422,139, thedisclosure of which is herein incorporated by reference in its entiretycould be used to slow or stop an automatic return system by the userdepressing the button during the retraction.

For example, FIGS. 54 and 55 illustrate another embodiment of thepresent invention including an embodiment of an instrument 3010 whereina retraction trigger 3121 is supported on the firing trigger 3020(similar to firing trigger 20 described herein above) for traveltherewith. More specifically, the retraction trigger 3121 is pivotallysupported on firing trigger pin 96 and protrudes through a slot (notshown) in the firing trigger 3020. A spring 3125 is attached between acoupling portion 3123 of the firing trigger 3020 and a mounting portion3127 of the retraction trigger 3121 to bias the retraction trigger 3121into an unactuated position. A second, normally-closed, retractionswitch 3131 is mounted within the handle and is oriented such that, asthe firing trigger 3020 is moved between a fully actuated position to afully unactuated position, an activation portion 3129 of the retractiontrigger 3121 does not activate the retraction switch 3131. However, themounting portion 3127 and activation portion 3129 of the retractiontrigger 3121 are so configured such that the activation portion 3129 maybe brought into activation contact with the retraction switch 3131 bydepressing the retraction trigger 3121 towards the firing trigger 3020regardless of where the firing trigger 3020 is located during theretraction process.

The embodiment shown in FIGS. 54-55 may also include various componentsthat operate in a manner similar that described herein above, forexample, with respect to FIG. 10. For example, reverse motor orend-of-stroke sensor 3130 and stop motor or beginning-of-stroke sensor3142 may operate in a manner similar to the respective sensors 130, 142described herein above. Mechanical components, 3122, 3078, 3072, 3070,3068, 3074, 3090 may operate in a manner similar to the respectivemechanical components 122, 78, 72, 68, 74, 90. Motor 3065 may operate ina manner similar to the motor 65. Also, the main drive shaft 3048 mayoperate in a manner similar to the main drive shaft 48 described hereinabove. For example, the main drive shaft 3048 may cause actuation of anend effector 12, including for example, actuation of a knife 32 and sled33.

As was discussed above, when the end effector 12 reaches the end of itsstroke, the end of stroke switch 3130 will be activated. As shown in theexample of FIG. 55, the retraction switch 3131 is in series with theend-of-stroke switch 3130. Because the retraction switch 3131 isnormally closed, the inductor 3134 of the relay 3132 will be energizedwhen both switches 3130, 3131 are closed. This causes the relay 3132 toassume its energized state, which causes current to bypass the cartridgelockout sensor 3136 and variable resistor 3110. Current flows to thedouble pole, double throw relay 3140 and to the motor 3065, but in amanner, via the relay 3140, that causes the motor 3065 to reverse itsrotational direction. Because the beginning-of-stroke switch 3142 isclosed, current will flow back to the relay 3132 to keep it closed untilthe switch 3142 opens. When the knife 32 is fully retracted, thebeginning-of-stroke switch 3142 is opened, thereby removing power fromthe motor 3065. If, however, the user wants to slow down the retractionprocess, the user may depress the retraction trigger 3121 to activatethe variable resistance portion 3133 of the retraction switch 3131. Whenthe retraction trigger 3121 is not depressed, the resistance of thevariable resistance portion 3133 is a minimum. When the trigger 3121 isdepressed, the resistance of the variable resistance portion 3133increases in proportion to the depressing force of the retractiontrigger 3121 to reduce the current to the motor 3065. Further depressionof the retraction trigger 3121 will slow the retraction process untilthe normally closed contact 3135 portion of the retraction switch 3131opens and stops the current flow to the motor 3065. In variousembodiments, once the user releases the retraction trigger 3121, thespring 3125 will move the retraction trigger 3121 to an unactuatedposition and the contact portion 3135 of switch 3131 will return to thenormally closed position and thereby permit current to flow again to themotor 3065 to complete the retraction process.

The unique and novel features of the retraction switch and retractiontrigger arrangements described above may also be employed in connectionwith the various embodiments disclosed in U.S. Patent ApplicationPublication No. US 2010/0076474 A1, now U.S. Pat. No. 8,210,411 and U.S.Pat. No. 7,422,139 which have both been herein incorporated by referencein their respective entireties. For example, FIG. 56 shows anotherembodiment of a current control circuit of the present invention. When(i) the run motor (or fire) switch 3110 is closed (it is shown in anopen state in FIG. 56), (ii) the safety switch 3240 is closed (it isshown open in FIG. 56) indicating that the device safety is set, and(iii) the normally-closed lockout switch 3242 is opened indicating thatthe instrument is not in a lock-out condition, current flows through thesafety switch 3240, through the lockout indicator 3244 (which may be aLED as shown in FIG. 56) to the motor 3065. When the end of the cuttingstroke is reached, the end-of-stroke or direction switch 3130 isswitched, reversing the direction of the motor 3065 (with the fireswitch 3110 also having been released). In this state, current alsoflows through a reverse direction indicator 3246, such as an LED,providing a visual indication that the motor direction has beenreversed.

As shown in FIG. 56, the circuit may also comprise a manual returnswitch 3248. The operator may manually actuate this switch if thecutting instrument 32 has only been partially fired. Switching themanual return switch 3248 causes the motor 3065 to reverse rotate,causing the cutting instrument 32 to return to its original or homeposition. If, the user desires to slow down or stop the retractionprocess, the user depresses the retraction trigger 3121 to activate thevariable resistance portion 3133 of the retraction switch 3131. When thetrigger 3121 is depressed, the resistance increases in proportion to thedepressing force to reduce the current to the motor 3065. Furtherdepression of the retraction trigger 3121 will slow the retractionprocess until the normally closed contact 3135 portion of the retractionswitch 3131 opens and stops the current flow to the motor 3065. Invarious embodiments, once the user releases the retraction trigger 3121,the spring 3125 will move the retraction trigger 3121 to an unactuatedposition and the contact portion 3135 of switch 3131 will return to thenormally closed position and thereby permit current to flow again to themotor 3065 to complete the retraction process.

Additional configurations for motorized surgical instruments aredisclosed in published U.S. Patent Application Publication No. US2010/0076474 A1, entitled MOTOR-DRIVEN SURGICAL CUTTING INSTRUMENT, nowU.S. Pat. No. 8,210,411 which is incorporated herein by reference in itsentirety. For example, FIG. 57 is a schematic diagram of another currentcontrol circuit according to various embodiments of the presentinvention. In various embodiments, the motor control circuit may includeone of more integrated circuits (ICs), such as, for example, aprocessor, memory, microcontroller, time circuits, etc. In otherembodiments, the motor control circuit may not comprise any ICs. Such anon-IC current control circuit may be advantageous because it is oftendifficult, complicated, and expensive to sterilize a surgical instrumentincluding ICs.

When an operator initially applies an actuation motion to the firingtrigger 3020 after locking the closure trigger 18, the run motor switch3110 is activated (or closed), allowing current to flow therethrough. Ifthe normally open reverse motor sensor switch 3130 is open (meaning theend of the end effector stroke has not been reached), current will flowto a single pole, double throw relay 3132. When the reverse motor sensorswitch 3130 is not closed, a coil 3134 of the relay 3132 will not beenergized, so the relay 3132 will be in its de-energized state.

As shown in FIG. 57C, the circuit may also include a resistive element3144 and a switch 3146 connected in parallel, with the paralleledelements connected in series with the relay 3132. The resistive element3144 and the switch 3146 are also connected to the power source 3064.The switch 3146 may be controlled by a control circuit 3135 that isresponsive to the cutting instrument position sensor 3150. According tovarious embodiments, the control circuit 3135 may open the switch 3146when the cutting instrument 32 is (i) very near to the beginning of itsstroke and (ii) very near to the end of its stroke. For example, thecontrol circuit may open the switch when the cutting instrument 32 is(i) 0.001 inches from the beginning point of its stroke and (ii) 0.001inches from the end of its stroke, as determined by the cuttinginstrument position sensor 3150. With the switch 3142 open, currentflows through the resistive element 3144, and then through the relay3132, the relay 3138, the run motor sensor switch 3110, to the motor3065. Current flowing through the resistive element 3144 reduces themagnitude of the current delivered to the motor 3065, thereby reducingthe power delivered by the motor 3065. Thus, when the cutting instrument32 is (i) very near to the beginning of its stroke or (ii) very near tothe end of its stroke, the power delivered by the motor 3065 is reduced.Conversely, once the cutting instrument 32 moves sufficiently far fromits beginning point or end of stroke point, the control circuit 3135 mayclose the switch 3146, thereby shorting the resistive element 3144,thereby increasing the current to the motor 3065, thereby increasing thepower delivered by the motor.

Alternatively, the resistive element 3144 and switch 3146 may bereplaced by and/or supplemented with a pulse width modulation circuit3148, as illustrated in FIGS. 57, 57A, 57B. The pulse width modulationcircuit 3148, as shown, may be connected in series between the powersource 3064 and the motor 3065. The pulse width modulation circuit 3148may receive signals from the control circuit 3135 causing the circuit3148 to switch between an open and a closed circuit. The duty cycle orpulse width of the resulting signal may control the average current, andtherefore the power, provided to the motor 3065. When the cuttinginstrument 32 is near the beginning or the end of its stroke, the pulsewide modulation circuit 3148 may decrease the duty cycle or pulse widthof the current provided to the motor 3065, thus reducing the deliveredpower.

According to various embodiments, the current control circuit furtherincludes lockout sensor switches 3136 a-d collectively defining aninterlock circuit 3137 through which current from the relay 3132, whende-energized, passes in order for electrical operation of the motor 3065to be initiated. Each lockout sensor switch 3136 a-d may be configuredto maintain an open (i.e., non-conductive) switch state or a closed(i.e., conductive) switch state responsive to the presence or absence,respectively, of a corresponding condition. Any of the correspondingconditions, if present when the instrument 10 is fired, may result in anunsatisfactory cutting and stapling operation and/or damage to theinstrument 10. Conditions to which the lockout sensor switches 3136 a-dmay respond include, for example, (a) the absence of the staplecartridge 34 in the channel 22, (b) the presence of a spent (e.g.,previously fired) staple cartridge 34 in the channel 22, and (c) an open(or otherwise insufficiently closed) position of the anvil 24 withrespect to the channel 22. Other conditions to which the lockout sensorswitches 3136 a-d may respond, such as component wear, may be inferredbased upon an accumulated number of firing operations produced by theinstrument 3010. Accordingly, in various embodiments, if any of theseconditions exists, the corresponding lockout sensor switches 3136 a-dmaintain an open switch state, thus preventing passage of the currentnecessary to initiate operation of the motor 3065. Passage of current bythe lockout sensors 3136 a-d is allowed, in various embodiments, onlyafter all of the conditions have been remedied. It will be appreciatedthat the above-described conditions are provided by way of example only,and that additional lockout sensor switches for responding to otherconditions detrimental to operation of the instrument 3010 may beprovided. It will similarly be appreciated that for embodiments in whichone or more of the above-described conditions may not exist or are of noconcern, the number of lockout sensor switches may be fewer than thatdepicted.

As shown in FIG. 57, the lockout sensor switch 3136 a may be implementedusing a normally open switch configuration such that a closed switchstate is maintained when the staple cartridge 34 is in a positioncorresponding to its proper receipt by the channel 22. When the staplecartridge 34 is not installed in the channel 22, or is installedimproperly (e.g., mis-aligned), the lockout sensor switch 3136 amaintains an open switch state. Lockout sensor switch 3136 b may beimplemented using a normally open switch configuration such that aclosed switch state is maintained only when an unspent staple cartridge34 (i.e., a staple cartridge 34 having a sled 3033 in the unfiredposition) is present in the channel 22. The presence of a spent staplecartridge 34 in the channel 22 causes the lockout sensor switch 3136 bto maintain an open switch state. Lockout sensor switch 3136 c may beimplemented using a normally open switch configuration such that aclosed switch state is maintained when the anvil 24 is in a closedposition with respect to the channel 22. The lockout sensor switch 3136c may be controlled in accordance with a time delay feature wherein aclosed switch state is maintained only after the anvil 24 is in theclosed position for a pre-determined period of time.

Lockout sensor switch 3136 d may be implemented using a normally closedswitch configuration such that a closed switch state is maintained onlywhen an accumulated number of firings produced by the instrument 3010 isless than a pre-determined number. The lockout sensor switch 3136 d maybe in communication with a counter 3139 configured for maintaining acount representative of the accumulated number of firing operationsperformed by the instrument 3010, comparing the count to thepre-determined number, and controlling the switch state of the lockoutsensor switch 3136 d based upon the comparison. Although shownseparately in FIG. 57, it will be appreciated that counter 3139 may beintegral with the lockout sensor switch 3136 d so as to form a commondevice. Preferably, the counter 3139 is implemented as an electronicdevice having an input for incrementing the maintained count based uponthe transition of a discrete electrical signal provided thereto. It willbe appreciated that a mechanical counter configured for maintaining thecount based upon a mechanical input (e.g., retraction of the firingtrigger 3020) may be used instead. When implemented as an electronicdevice, any discrete signal present in the electrical circuit thattransitions once for each firing operation may be utilized for thecounter 3139 input. As shown in FIG. 57, for example, the discreteelectrical signal resulting from actuation of the end-of-stroke sensor3130 may be utilized. The counter 3139 may control the switch state oflockout sensor switch 3136 d such that a closed switch state ismaintained when the maintained count is less than a pre-determinednumber stored within the counter 3139. When the maintained count isequal to the pre-determined number, the counter 3139 causes the lockoutsensor switch 3136 d to maintain an open switch state, thus preventingthe passage of current therethrough. It will be appreciated that thepre-determined number stored by the counter 3139 may be selectivelyadjusted as required. According to various embodiments, the counter 3304may be in communication with an external display (not shown), such as anLCD display, integral to the instrument 3010 for indicating to a usereither the maintained count or the difference between the pre-determinednumber and the maintained count.

According to various embodiments, the interlock circuit 3137 maycomprise one or more indicators visible to the user of the instrument3010 for displaying a status of at least one of the lockout sensorswitches 3136 a-d. More details regarding such indicators may be foundin published U.S. Patent Application Publication No. 2007/0175956,entitled ELECTRONIC LOCKOUTS AND SURGICAL INSTRUMENT INCLUDING SAME, nowU.S. Pat. No. 7,644,848, which is incorporated herein by reference inits entirety. This application also includes example mountingarrangements and configurations for the lockout sensor switches 3136a-d.

In the illustrated embodiment, when the lockout sensor switches 3136 a-dcollectively maintain a closed switch state, a single pole, single throwrelay 3138 is energized. When the relay 3138 is energized, current flowsthrough the relay 3138, through the run motor switch sensor 3110, and tothe motor 3065 via a double pole, double throw relay 3140, therebypowering the motor 3065, allowing it to rotate in the forward direction.According to various embodiments, because the output of the relay 3138,once energized, maintains the relay 3138 in an energized state untilrelay 332 is energized, the interlock circuit 3137 will not function toprevent operation of the motor 3165 once initiated, even if one or moreof the interlock sensor switches 3136 a-d subsequently maintains an openswitch state. In other embodiments, however, it may be necessary orotherwise desirable to connect the interlock circuit 3137 and the relay3138 such that one or more the lockout sensor switches 3136 a-d mustmaintain a closed switch state in order to sustain operation of themotor 3165 once initiated.

Rotation of the motor 3065 in the forward direction causes the ring tomove distally and thereby de-actuate the stop motor sensor switch 3142in various embodiments. Because the switch 3142 is normally closed, asolenoid 3141 connected to the switch 3142 may be energized. Thesolenoid 3141 may be a conventional push-type solenoid that, whenenergized, causes a plunger (not shown) to be axially extended.Extension of the plunger may operate to retain the closure trigger 18 inthe retracted position, thus preventing the anvil 24 from opening whilea firing operation is in progress (i.e., while the switch 3142 is notactuated). Upon de-energization of the solenoid 3141, the plunger isretracted such that manual release of the closure trigger 18 ispossible.

When the actuation member portion reaches the distal most end of itsstroke, the reverse motor switch 3130 will be activated, thereby closingthe switch 3130 and energizing the relay 3132. This causes the relay3132 to assume its energized state, which causes current to bypass theinterlock circuit 3137 and run motor sensor switch 3110, and insteadcauses current to flow to both the normally-closed double pole, doublethrow relay 3140 and back to the motor 3065, but in a manner, via therelay 3140, that causes the motor 3065 to reverse its rotationaldirection. Because the stop motor sensor switch 3142 is normally closed,current will flow back to the relay 3132 to keep it energized until theswitch 3142 opens. When the knife 32 is fully retracted, the stop motorsensor switch 3142 is activated, causing the switch 3142 to open,thereby removing power from the motor 3065, and de-energizing thesolenoid 3141.

In the embodiment depicted in FIG. 57, a normally closed retractionswitch 3143 is employed which interfaces with retraction trigger 3121(not shown in FIG. 57). When retraction switch 3143 is activated, itopens to stop the flow of current to the motor 3065. In alternativeembodiments (FIG. 57A), the normally closed retraction switch 3143 couldbe replaced with a variable resistor 3143′ that interfaces withretraction trigger 3121. In such embodiment, when the retraction trigger3121 is not depressed, the resistance of the variable resistor isminimal to allow maximum current to flow to the motor 3065. Whendepressed the resistance increases in proportion to the depressing forceto reduce current to the motor. Such variable resistor may also bereplaced with the retraction switch 3131 as described above (see FIG.57B).

Accidental actuation prevention for a powered endocutter: With theintroduction of powered systems that no longer limit the device functionto the force capabilities of the user, inadvertent initiation of thefiring cycle may become a much more prevalent issue. It will beincreasing ease to “bump” the activation control and have the instrumentbegin firing thereby tripping the lockout of the cartridge or even“jamming” it on tissue, as the user is unaware it has already begunfiring. Various lockout arrangements are disclosed in U.S. Pat. No.7,644,848, entitled ELECTRONIC LOCKOUTS AND SURGICAL INSTRUMENTINCLUDING SAME to Swayze et al., the disclosure of which is hereinincorporated by reference in its entirety. To eliminate this issuesecondary unlock activator switches or buttons could be used to unlockthe firing mechanism. This is much the same as the two switch systemsused in the power saw industry as well as the military to protectagainst accidental actuation. The secondary switch can either releasethe lock on the firing trigger or merely energize the power to thecontrol.

As mentioned above, in using a two-stroke motorized instrument, theoperator first pulls back and locks the closure trigger 18. FIGS. 58 and59 show one embodiment of a way to lock the closure trigger 18 to thepistol grip portion 3026 of the handle 3006. In the illustratedembodiment, the pistol grip portion 3026 includes a hook 3150 that isbiased to rotate CCW about a pivot point 3151 by a torsion spring 3152.Also, the closure trigger 18 includes a closure bar 3154. As theoperator draws in the closure trigger 18, the closure bar 3154 engages asloped portion 3156 of the hook 3150, thereby rotating the hook 3150upward (or CW in FIGS. 58 and 59) until the closure bar 3154 completelypasses the sloped portion 3156 passes into a recessed notch 3158 of thehook 3150, which locks the closure trigger 18 in place. The operator mayrelease the closure trigger 18 by pushing down on a slide button release3160 on the back or opposite side of the pistol grip portion 3026.Pushing down the slide button release 3160 rotates the hook 3150 CW suchthat the closure bar 3154 is released from the recessed notch 3158.Other arrangements for releasably locking the closure trigger 18 aredisclosed in U.S. Pat. No. 7,422,139 which has been herein incorporatedby reference.

As can be seen in FIGS. 58 and 59, in various embodiments, a closurelock switch 3151 may be mounted in the hook 3150 such that that isactivated only when the hook 3150 is latched in place. However, theclosure lock switch 3151 may be mounted in the pistol grip portion 26for activation by the closure trigger 18 when the closure trigger 18 islocked in position. In still other alternative embodiments, the closurelock switch 3151 is mounted to the end effector 12 such that it isactivated only when the anvil or other movable portion is in the“closed” position. Regardless of the specific location of the closurelock switch 3151, in various embodiments, the closure lock switch 3151is a normally open switch that will be closed upon locking of theclosure trigger 18 or otherwise manipulating the end effector to a“closed” position.

FIG. 60 is a schematic diagram of an electrical circuit of theinstrument 3010 according to various embodiments of the presentinvention illustrating the use of the closure lock switch 3151. As canbe seen in that Figure, current will not be permitted to flow from thebattery 3064 to the motor 3065 even if a cartridge is present unless theclosure lock switch 3151 is closed. Thus, the motor 3065 cannot beoperated unless the closure trigger is in the locked closed positionwhich also reflects that the end effector is in the closed state.

Various embodiments may further include a start switch 3153 that must beactivated by the surgeon before current will be permitted to flow fromthe battery 3064 to the other circuit components and ultimately to themotor 3065. Start switch 3153 is normally open and may be located at aconvenient location on the handle 3006. See FIG. 61. Thus, in theseembodiments, even if the end effector 12 contains a cartridge and theclosure trigger 18 is locked in a closed position, current will not bepermitted to flow to the motor 3065 until the start switch 3153 isclosed by the surgeon. In alternative embodiments, the start switch 3153may comprise a mechanical switch that prevents the firing trigger 3020from being physically rotated toward the pistol grip portion unless theswitch 3153 is moved to an actuated position.

Active adjustable staple height for a powered endocutter: Staple heightthat is adjustable to the tissue thickness and type has been pursued formany years. Most recently, U.S. patent application Ser. No. 11/231,456,filed Sep. 21, 2005, now U.S. Pat. No. 7,407,078 and U.S. patentapplication Ser. No. 11/540,735, filed Sep. 29, 2006, now U.S. Pat. No.7,467,740, the disclosures of which are each hereby incorporated byreference in their respective entireties generally involve a flexiblecoupling member or supports that would allow the gap of the instrumentto enlarge with loads induced by thicker tissue in the device. This“passive” variable staple height allows the thickness of the tissue tocreate larger staple forms.

With the introduction of a power source within the instrument thisallows for the use of electricity to change the height of an internalelement within the dynamic coupling element with would change the heightof the staple “actively” by the surgeon or instrument setting thedesired height. This internal element could be a shape memory materialand the electricity changes its temperature and therefore allows it tochange its physical height due to preset configuration. Another viablemethod would be the inclusion of an electro-active polymer (EAP) thatthrough the introduction of an electric field allows it to change itsheight and width. Yet a third embodiment would be to utilize atraditional linear electrical stepper element that can ratchet a smalladjustable screw element within the coupling beam that would adjust itsheight.

More specifically and with reference to FIGS. 62 and 63, an end effector12 of various embodiments of the present invention is shown incross-section with the anvil 24 in a closed or clamped position. As canbe seen, the cutting instrument or knife 32 has a lower actuator portion37 that has a threaded sleeve or nut portion 37′ that is configured tothreadably engage the helical screw shaft 36. In addition, a fin 39protrudes laterally from each lateral side of the nut portion 37 toconfront corresponding slide portions 3023 of the channel 22. As canalso be seen in FIG. 62, the knife 32 has an upper actuator portion 41that is sized to be received within a longitudinal T-shaped slot 43 inthe anvil 24. As can be seen in FIG. 62, a pair of upper retainer pins41′ protrude laterally from each side of the upper actuator portion 41of the knife 32. Each upper retainer pin 41′ is configured to extendinto a corresponding portion of the T-shaped slot 43 provided in theanvil 24. Thus, as the knife 32 is driven distally through the endeffector 12, the fins 39 and the retainer pins 41′ serve to limit theamount of space between the anvil 24 and the cartridge 34 to a maximumamount of predetermined space.

Various embodiments of the present invention are provided with means foradjusting the amount of space between the anvil 24 and the cartridge 34installed within the channel 22. For example, in some embodiments, eachfin 39 supports a sled contact 3045 for sliding contact withcorresponding electrical contacts 47 that are mounted within each slideportion 3023 of the channel 22. The electrical contacts 47 are elongatedand extend within the channel 22 so that the sled contacts 3045 arealways on contact with their corresponding electrical contact 47 as theknife 32 is driven within the channel 22. Electrical contacts 47 areconnected to the power source or battery 3064 and are configured toreceive current therefrom when the motor 3065 is powered to drive theknife 32 distally. Also in certain embodiments, an electricallyresponsive height adjustment member 49 is mounted to each retainer pin41′ as shown in FIG. 62. The height adjustment members 49 areelectrically coupled to the sled contacts 3045 to receive electricalcurrent therefrom. In various embodiments, the height adjustment members49 may comprise shape memory material that, when electrified, changesits physical height due to a preset configuration. Thus, depending uponthe amount of current received, the height adjust member members 49 mayexpand and force the anvil 24 towards the cartridge 34 to thereby reducethe amount of space therebetween. The amount that such material isproportional to the amount of current received and is known. A controlcircuit (not shown) may be employed to control the amount of expansionand hence the amount of space between the anvil 24 and the cartridge 34.In other embodiments, the height adjustment material comprises anelectro-active polymer (EAP) that is retained within a pocket in the pin41 or is otherwise attached thereto.

FIG. 64 illustrates another embodiment that is similar to the embodimentdepicted in FIG. 62. However, in this embodiment, the height adjustmentmembers 49 are mounted in the anvil 24 and receive current from thepower source through conductors attached directly thereto. Thus, in thisembodiment, the contacts 43 and 3045 as described above are not needed.

FIG. 65 illustrates an alternative knife assembly 32′ that issubstantially identical to the knife assembly 32 described above, exceptthat the retainer pins 41′ are mounted to a separate upper actuatorportion 3302 that is selectively movable in a vertical direction “VD”relative to a lower portion 3300 of the knife assembly 32′. A secondmotor 3304 may be mounted to the lower portion 3300 and have a leadscrew 3306 that threadably engages a nut portion 3308 of the upperretainer portion 3302. The upper retainer portion has a “T”-shapedtongue portion 3310 that slidably extends into a correspondingly shapedslot 3312 in the lower portion 3300 to prevent rotation of the upperretainer portion 3302 relative to the lower retainer portion 3300 whilepermitting the upper retainer portion 3302 to move vertically relativethereto. Thus, the distance between the upper and lower retainerportions 3302, 3300 may be adjusted by powering the second motor 3304.Accordingly, if the surgeon wants to reduce the amount of space betweenthe anvil 24 and the cartridge 34, second motor 3304 is powered torotate in a first direction to draw the upper retainer portion 3302towards the lower retainer portion 3300. If however, the surgeon desiresto increase the amount of space between the anvil 24 and the cartridge34, the second motor 3304 is rotated in an opposite direction.

Various embodiments of the present invention include end-effectorillumination methods and methods for illuminating the surgical site whenemploying a powered endocutter. Currently when the end-effector is in ornear its deployment position it is sometimes difficult for the surgeonto visualize the treatment site as there are shadows cast by adjacentstructures as well as the end-effector may even be behind anotherstructure entirely. FIG. 66 illustrates in general form, a distal end3402 of a surgical stapler 3400 of various embodiments of the presentinvention which includes an anvil 3404, a cartridge body 3406, andchannel 3408. As seen from that Figure, an additional light source 3410may be positioned on the end of the cartridge body 3406 to illuminatetissue 3401. This light source 3410 could be any combination ofpractical means that convert electrical energy to light including butnot limited to semiconductor (such as LED), a conventional incandescentor filament bulb, electroluminescent or laser that may be powered from abattery supported in the instrument handle or in other embodiments,powered by alternating current. Such arrangements would allow thesurgeon to not only light up the treatment site directly, they couldallow for backlighting of structures to see the internal components likevasculature and facilitate the use of a laser pointer through atraditional scope to point out areas of interest to others.

In various embodiments, one or more contacts 3420 are provided on theback of the cartridge body 3406 that are configured to engage contacts3422 within the channel 3408. See FIG. 67. This would allow the surgeonto energize the light 3410 as needed by energizing contact set via aswitch positioned on the handle 3430. This switch could even havevariable intensity as the one described in could control the actuationspeed of the main, device. Other lighting arrangements for lighting theend of an anvil attached to a circular surgical stapler are disclosed inU.S. Pat. No. 7,918,377, entitled SURGICAL STAPLING INSTRUMENT WITHAPPARATUS FOR PROVIDING ANVIL POSITION FEEDBACK, the entire disclosureof which is hereby incorporated by reference.

U.S. Pat. No. 8,708,213, entitled SURGICAL INSTRUMENT HAVING A FEEDBACKSYSTEM, the entire disclosure of which is hereby incorporated byreference, further discloses in FIGS. 45-47 of that Publication outputdisplays that could show among other this position feedback of theend-effector, lockout status, number of firings etc. This would minimizeone of the more difficult issues for the user, which is theidentification of the status of a device, especially the lockout statusof the device without actuating the device. An additional feedback thatwould be helpful for the user would be immediate feedback as to thestatus of the cartridge when it is loaded. As in the above applicationit could be rolled up into the lockout indication on the handle 3430. Anindicator 3432 (such as an LED, glass bulb, LCD, sonic enunciator,vibrator, etc.) could solely be associated with the status of acartridge lockout means or mechanism such that it providing thisinformation to the surgeon. This LED could be located on the handle3430. See FIG. 69. Alternatively an indicator 3434 could be located nearthe distal end 3402 which would provide immediate information to thesurgeon and loader if the cartridge is “good to go” or not. See FIG. 68.This can be accomplished with a switch or set of contacts associateddirectly with the mechanical lockout. The switch or contacts complete acircuit such that the indicator provides appropriate information. Thiscompleted contact set could be through a conductive element within thesled (part 33 in U.S. Patent Application Publication No. US2007/0175958, now U.S. Pat. No. 7,766,210) and the two contacts could bein the proximal position of the channel (part 22). Another way to detectlockout status is indirectly through instrument status (example 1:loaded cartridge and no attempt to fire would indicate lockout is notengaged; example 2: fired instrument and no new cartridge installedwould indicate lockout is engaged; etc.). Another embodiment would be toplace the LED or visual indication cue on the cartridge itself. When thecartridge is snapped into place it creates a contact that supplies thecartridge with power. Should the cartridge be fired not only does themechanical lockout stop the advancement of the knife the cartridgecircuit light up the LED on the cartridge informing the surgeon on thescope monitor that the cartridge is locked out. This could be furtherexpanded by placing a small battery or other charge accumulator withinthe cartridge itself to eliminate the need for a power connection to themain device. Also the cartridge circuit could be set to light thelockout light whenever the device is closed to inform the user there isa spent cartridge in the device.

Indication feedback for powered articulation and cartridge color:Indicating the type of cartridge installed (color) and angle ofarticulation is considered useful to the surgeon. The indication ofarticulation angle could be indicated in several ways includingnumerically or graphically as in an arc of LEDs. The location of thisindication could be on the handle in a convenient location or on theshaft of the device just proximal to the end-effector. The end-effectorfeedback could be passive or active. The active would light upadditional LEDs to show the angle. The passive could just show a halfpie lighted up so the surgeon could intuit how articulated theend-effector is. As we further explore the surgical procedures itbecomes more and more obvious that the surgeon's eyes need to be on thesurgical site not on the handle of the instrument. We also begin tounderstand the surgeon's need for complete status feedback from thedevice. Articulation angle could be illuminated as part of thearticulation joint itself. With lights, LEDs, etc. denoting thediffering angle or even a small LCD denoting angle in degrees. Thiswould allow the surgeon to have some feedback on the angle off ofstraight so he/she can easily navigate back to this angle after removaland reinsertion. Another issue is “obvious” indication of what colorcartridge is in the device. This can be accomplished by a color codedlight array on either the end-effector or the cartridge. Thisinformation could also be transmitted back to the handle to display a“redundant” display to assure there is minimal confusion as to whatcartridge is in the jaws. Another improvement could include a small leafspring contact connected to the proximal deck of the cartridge thatindicates if a minimum tissue pressure has been achieved within thejaws. This minimum pressure would at the very least indicate if a thicktissue cartridge is being used in thin tissue applications, as it wouldnot light if insufficient tissue pressure on the deck were present.

There is a possible need of a method for the introduction of non-sterilebattery packs (possibly with the electronics integral to the batterypack if programmable logic becomes a key customer need). A patentalready exists within the orthopedic drill industry for the insertion ofa non-sterile battery pack within a separately sterilized re-useabledevice. This innovation is intended to improve that concept by utilizingthe disposable device sterile packaging to protect the sterility of theinstrument during the insertion of the non-sterile battery pack. Afurther improvement would be the inclusion of a “hatch” door designedwithin the instrument and closable after the pack has been inserted butbefore the device is removed from the final sterile packaging. Thishatch would then “contain” the non-sterile battery that couldcontaminate the sterile surgical field. The method here would be toinclude an additional layer of packaging that would have a perforatedarea that the battery could be pushed through, either rupturing theextra layer and allowing the battery through or going with the electrodeset of the battery only to be ruptured by the exposable pin tips of thebattery at complete insertion. An alternative of this would be to havethe internal terminals of the gun (deep inside the battery protectioncavity) rupture the sterile barrier and seat within pinholes in thebattery pack. The hatch could then be closed through the sterile packsealing the system. The gun could then be handed into the sterile fieldnormally as any sterile device could.

Position Locator Embodiments/Linear encoder and load control of motorparameters: U.S. Pat. Nos. 6,646,307 and 6,716,223 disclose themechanisms for the measurement of rotation and related torque to controlmotor parameters and optimizing of those parameters based onidentification of end-effector configurations and loading. U.S. Pat. No.7,766,210 shows a method through the use of a threaded length of theprimary shaft in FIGS. 8-13 how this type of linear motion control couldbe used to control the trigger location. The same type of method couldbe used for electronic linear control methods. The end-effector couldidentify its length and type mechanically by depressing at least onespring biased plunger, which could identify to the handle the type, andlength it would allow the motor to run. The motor rotation could beconverted from rotary motion to linear rack or cable motion, which couldthen be used to adjust motor voltage, current, and speed to affect thedesired linear motion of the control slide. The control slide could thenbe directly coupled to the knife drive motion. This control slide couldhave discrete or continuous “stop” locations that the plunger identifiermarks as the max “go to” linear displacement before retraction

Identification of modular reloads with linear drive: A useful featurefor a surgical instrument is the ability to identify which end-effectorhas been attached to the instrument. In the case of a powered surgicalstapler, several different types of end-effectors could be attached.Additionally, a type of end-effector may have at least one functionand/or feature that is selectively utilized or enabled. Disclosed aremeans for identifying which end-effector is attached. Note that the“type” of end-effector referenced below is not limited to mechanical,pneumatic or hydraulically coupled end-effectors. The instrument maytake different actions, adjust operating parameters, indicate availablefunctions etc. as a result of detecting this end effector.

The end-effector has an electrical connection that is made when it isattached to the instrument. The instrument communicates with theend-effector and reads at least one of several types of signals. Aswitch position or contact position indicates which type of end-effectoris present. A passive element is measured for impedance and the resultindicates which type of end-effector is present.

The end-effector has a radio frequency link to the instrument and datais transferred in at least one direction between the end-effector andthe instrument.

The end-effector has an acoustic link to the instrument and data istransferred in at least one direction between the end-effector and theinstrument.

The end-effector has an optical link to the instrument and data istransferred in at least one direction between the end-effector and theinstrument.

The end-effector has mechanical link that engages elements (such asswitches or contacts) in the instrument that identify it and therebydata is transferred in at least one direction between the end-effectorand the instrument.

While the present invention has been illustrated by description ofseveral embodiments and while the illustrative embodiments have beendescribed in considerable detail, it is not the intention of theapplicant to restrict or in any way limit the scope of the appendedclaims to such detail. Additional advantages and modifications mayreadily appear to those skilled in the art.

For example, although the embodiments described above have advantagesfor an endoscopically employed surgical severing and stapling instrument10, a similar embodiments may be used in other clinical procedures. Itis generally accepted that endoscopic procedures are more common thanlaparoscopic procedures. Accordingly, the present invention has beendiscussed in terms of endoscopic procedures and apparatus. However, useherein of terms such as “endoscopic”, should not be construed to limitthe present invention to a surgical instrument for use only inconjunction with an endoscopic tube (i.e., trocar). On the contrary, itis believed that the present invention may find use in any procedurewhere access is limited to a small incision, including but not limitedto laparoscopic procedures, as well as open procedures.

Any patent, publication, or information, in whole or in part, that issaid to be incorporated by reference herein is incorporated herein onlyto the extent that the incorporated material does not conflict withexisting definitions, statements, or other disclosure material set forthin this document. As such the disclosure as explicitly set forth hereinsupersedes any conflicting material incorporated herein by reference.

While this invention has been described as having exemplary designs, thepresent invention may be further modified within the spirit and scope ofthe disclosure. This application is therefore intended to cover anyvariations, uses, or adaptations of the invention using its generalprinciples. Further, this application is intended to cover suchdepartures from the present disclosure as come within known or customarypractice in the art to which this invention pertains.

1-24. (canceled)
 25. A stapling assembly, comprising: a frame; a distalend; a first jaw comprising a channel; a channel retainer, wherein saidchannel is slidably attachable to said channel retainer; a second jawextending from said frame; a plurality of staples; a staple firingmember comprising a first cam configured to engage said first jaw and asecond cam configured to engage said second jaw when said staple firingmember is advanced from an unadvanced position toward said distal end,wherein said first cam and said second cam are configured toco-operatively hold said first jaw and said second jaw relative to oneanother when said staple firing member is advanced toward said distalend, and wherein one of said first jaw and said second jaw comprises aclearanced opening configured to receive one of said first cam and saidsecond cam such that said first jaw is not held to said second jaw whensaid staple firing member is in said unadvanced position; and a lockoutconfigured to block the advancement of said staple firing member whensaid channel is not attached to said channel retainer.
 26. A staplingassembly, comprising: an elongate shaft; a first jaw; a second jaw,wherein said first jaw is rotatable relative to said second jaw; adetachable cartridge portion comprising a plurality of staples; a staplefiring member comprising a first cam configured to engage said first jawand a second cam configured to engage said second jaw when said staplefiring member is advanced from an initial position, and wherein saidfirst jaw comprises a clearanced opening configured to receive saidfirst cam when said staple firing member is in said initial positionsuch that said first cam is not engaged with said first jaw when saidstaple firing member is in said initial position; and a lockoutconfigured to block the advancement of said staple firing member whensaid detachable cartridge portion is not attached to said staplingassembly.